Barcelona 4-0 Manchester City, Arsenal 6-0 Ludogorets: Champions League as it happened

That is all from us for now, but make sure you check back in with IBTimes UK tomorrow night as we bring you live coverage of the Europa League. Manchester United host Robin van Persie and Fenerbahce, while Claude Puel's Southampton travel to the San Siro to take on Inter Milan.

Don't miss it. Goodnight.

The Arsenal juggernaut rolls on unabated after the Gunners put Ludogorets to the sword with six goals and a first career hat-trick for Mesut Ozil. They continue to top Group A ahead of PSG courtesy of their superior goal difference. Wenger's men, who have now won seven straight matches in all competitions travel to Bulgaria in 13 days time.

You can read IBTimes UK sport editor Nick Howson's on the whistle report from north London here.

So a truly chastening evening for Guardiola, who returns to the Nou Camp and suffers the joint-heaviest defeat of his stellar managerial career so far.

City did not actually play particularly badly for much of this game, but multiple defensive errors and that idiotic dismissal by Bravo really served to undermine their efforts. Pep will be hoping for a much better outcome when Barcelona, who never really needed to get out of third gear here, visit the Etihad Stadium for the return fixture on 1 November.

City remain second in Group C, five points adrift of tonight's opponents after one win, one draw and one defeat from their opening three matches. Celtic, meanwhile, sink to the bottom after their disappointing home defeat to an out of form and undermanned Gladbach side in Glasgow.

Full-time scores

Group C

Barcelona 4-0 Manchester City

Celtic 0-2 Borussia Monchengladbach

Group D

Bayern Munich 4-1 PSV Eindhoven

FC Rostov 0-1 Atletico Madrid

Full-time scores

Group A

Arsenal 6-0 Ludogorets Razgrad

Paris Saint-Germain 3-0 FC Basel

Group B

Dynamo Kiev 0-2 Benfica

Napoli 2-3 Besiktas

Goal: Paris Saint-Germain 3-0 Basel (Edinson Cavani)

Looking to atone for that penalty miss, Neymar completes the rout by slaloming past Gundogan and Stones before wrapping a right-footed shot beyond Caballero.

What a lovely goal. Guardiola's humiliation is complete.

Goal: Barcelona 4-0 Manchester City (Neymar)

Goal: Napoli 2-3 Besiktas (Vincent Aboubakar)

Messi weaves his way through a hapless City defence before being felled by a sliding challenge from Clichy.

Referee Mazic immediately points to the spot and Caballero saves Neymar's penalty low to his right.

A brief moment of cheer for the visitors at least.

Penalty to Barcelona

Utterly ruthless from Arsenal and Ozil joins Messi in completing his treble. Perez is again the provider, teeing up his teammate with a lofted pass that is volleyed low past Stoyanov at his near post.

That is Ozil's first career hat-trick in senior football.

Goal: Arsenal 6-0 Ludogorets (Mesut Ozil)

Arsenal pile on yet more misery in north London. Oxlade-Chamberlain releases substitute Lucas Perez, who picks out Ozil all alone in the penalty area.

The German playmaker drives his effort into the ground and it loops up and into the back of the net.

Goal: Arsenal 5-0 Ludogorets (Mesut Ozil)

Goal: Bayern Munich 4-1 PSV Eindhoven (Arjen Robben)

Goal: Celtic 0-2 Borussia Monchengladbach (Andre Hahn)

Speaking of ridiculous red cards, that is utterly brainless from Mathieu. The centre-back, who replaced Pique in the first half, receives his second caution in quick succession for scything down Sterling near the touchline.

Enrique will be rightly furious with his defender, who should know better. We are level at 10-men apiece.

Red card: Jeremy Mathieu (Barcelona)

City are at sixes and sevens at the back. That is music to the ears of Messi, who taps home Suarez's pass from near the penalty spot to complete his 37th - yes, 37th - Barcelona hat-trick.

It's a testament to that unbelievable scoring prowess that he has still managed to notch three tonight, despite not playing particularly brilliantly according to his usual high standards.

IBTimes UK sport editor Nick Howson at the Emirates Stadium:

Arsenal have been at their clinical best at the start of this second half and Ludogorets are now on the wrong end of a rout. Oxlade-Chamberlain made it three before Mesut Ozil staked his claim for touch of the match with a delightful piece of control before making it four.

Goal: Barcelona 3-0 Manchester City (Lionel Messi)

Goal: Napoli 2-2 Besiktas (Manolo Gabbiadini)

Goal: Dynamo Kiev 0-2 Benfica (Franco Cervi)

Goal: Bayern Munich 3-1 PSV Eindhoven (Robert Lewandowski)

Barcelona have certainly not been at their vintage best tonight, but it was asking a lot for City to keep them at bay with 10 men.

After De Bruyne sloppily concedes possession with a rogue pass, Iniesta quickly takes control and finds Messi.

The pass is slightly behind him, but the Argentine superstar is still able to shift the ball inside Nicolas Otamendi and shoot under Caballero.

Game over.

Goal: Barcelona 2-0 Manchester City (Lionel Messi)

Goal: FC Rostov 0-1 Atletico Madrid (Yannick Ferreira Carrasco)

Goal: Paris Saint-Germain 2-0 Basel (Lucas)

Goal: Celtic 0-1 Borussia Monchengladbach (Lars Stindl)

After a long stoppage in play to treat his injured foot, Zabaleta is replaced by Clichy. Reserve goalkeeper Willy Caballero has also come on for Nolito following Bravo's red card.

Oh, Claudio Bravo.

The goalkeeper's return to the Nou Camp descends into a nightmare as he comes out to meet a sweeping ball forward only to gift possession straight to Suarez.

Well outside City's penalty box, he then blocks the Uruguayan's goalbound attempt with his hands and is promptly dismissed. What a shocking, mindless error. Has that all but ruined any hopes of a comeback for Guardiola's side?

Red card: Claudio Bravo (Manchester City)

Arsenal are threatening to run up a cricket score at the Emirates. German playmaker Ozil runs clear though on goal before maintaining his composure and sending a low shot beyond Stoyanov.

Goal: Arsenal 4-0 Ludogorets (Mesut Ozil)

A lightning quick start to the second half from Arsenal, who further extend their advantage just 39 seconds after the interval.

Gibbs' low cross from the left is not dealt with by Yordan Minev and Oxlade-Chamberlain steps up to confidently dispatch the rebound.

All too easy.

Goal: Arsenal 3-0 Ludogorets (Alex Oxlade-Chamberlain)

Half-time scores

Group C

Barcelona 1-0 Manchester City

Celtic 0-0 Borussia Monchengladbach

Group D

Bayern Munich 2-1 PSV Eindhoven

FC Rostov 0-0 Atletico Madrid

Half-time scores

Group A

Arsenal 2-0 Ludogorets Razgrad

Paris Saint-Germain 1-0 FC Basel

Group B

Dynamo Kiev 0-1 Benfica

Napoli 1-2 Besiktas

City are refusing to go down quietly in Barcelona. In fact, they are making the hosts look relatively pedestrian as they go in search of a deserved equaliser.

First John Stones heads agonisingly wide from a Silva free-kick, then De Bruyne prods into the side netting after Digne clearly handles Sterling's cross. That easily could have been a penalty.

Sandwiched between those two opportunities was a brilliant and theatrical double save from Bravo to thwart Suarez.

IBTimes UK sport editor Nick Howson at the Emirates Stadium:

Arsenal may have the lead but they go in at half-time knowing it could have been an all-so different story. On four separate occasions David Ospina denied Ludogorets from cancelling out Alexis Sanchez's sumptuous opener as Arsene Wenger's decision to select the Colombian over Petr Cech continues to pay dividends. The Bulgarians have refused to lie-down and go quietly here but they might have been silenced for good now by Theo Walcott's rasping strike from 25 yards.

Despite creating several chances, Arsenal have not had it all their own way tonight. Ludogorets have posed a threat on the counter and forced Ospina into one or two good saves. Brazilian midfielder Wanderson has also hit the post.

The Gunners have now doubled their lead, however. Mesut Ozil finds Theo Walcott with a pass to the edge of the penalty area and the England forward, whom Wenger insisted this week he never thought about selling during the summer, fires home his eighth goal of the season already.

Walcott also notched a brace against Swansea on Saturday and arguably should have scored two or three more.

Goal: Arsenal 2-0 Ludogorets (Theo Walcott)

Goal: Bayern Munich 2-1 PSV Eindhoven (Luciano Narsingh)

Goal: Paris Saint-Germain 1-0 Basel (Angel Di Maria)

Goal: Napoli 1-2 Besiktas (Vincent Aboubakar)

Ter Stegen is called into action to palm away a powerful low drive from Nolito. He then preserves Barcelona's lead with an impressive flying stop after Ilkay Gundogan breezes past an injured Pique, who is promptly replaced by Mathieu.

Barcelona's defensive injury woes continue.

Mathieu has been warming up on and off for the last few minutes, but it seems as if Enrique is keen to give Pique ever opportunity to prove his fitness.

Zabaleta again avoids a caution for bringing down Suarez. That must be his final warning.

Goal: Napoli 1-1 Besiktas (Dries Mertens)

Brave goalkeeping from Bravo to come racing off his line and thwart the threat of Neymar.

Messi then flights in a dangerous free-kick that is headed well wide by Ivan Rakitic. He should really have done better with that.

More defensive injury concerns for Enrique here as Pique, who appeared to take a knock earlier in the game, stays down in some discomfort after a heavy challenge from Silva.

He will need some treatment. The City man is booked for his troubles.

Barcelona turn the screw again quickly, but this time Suarez finds the side netting. Zabaleta is fortunate to avoid a yellow card for a blatant foul on Neymar.

Goal: Bayern Munich 2-0 PSV Eindhoven (Joshua Kimmich)

City have played without fear during the opening exchanges at the Nou Camp, but still they fall behind thanks to the irrepressible Messi.

After driving forward, the five-time Ballon d'Or winner feeds Iniesta. He looks unlikely to get to the return pass, but a crucial slip from Fernandinho allows him to regain possession and glide beyond Bravo before slotting the ball home.

The rest of City's defence just watched on helplessly as he notched his 87th Champions League goal.

Goal: Napoli 0-1 Besiktas (Adriano)

Goal: Barcelona 1-0 Manchester City (Lionel Messi)

IBTimes UK sport editor Nick Howson at the Emirates Stadium:

Arsenal are unlikely to grab any of the headlines tonight, but you'll have to go a long way to find a better goal than the one from Alexis Sanchez which has given the home side the lead. It was almost wasted on minnows Ludogorets, who were powerless as the Chilean scythed through and chipped Vladislav Stoyanov.

Arsenal have had a lot of early joy against that Ludogorets backline and they make their attacking superiority count with less than 15 minutes on the clock.

It's a wonderful effort from Sanchez, who drifts in from the left and cuts inside Cosmin Coti before beating Vladislav Stoyanov with a wonderful lofted finish. Brilliant goal.

Goal: Arsenal 1-0 Ludogorets (Alexis Sanchez)

Goal: Bayern Munich 1-0 PSV Eindhoven (Thomas Muller)

Alba's return to the starting lineup lasts just nine minutes. The left-back is a picture of disappointment as he trudges off to be replaced by Digne.

Goal: Dynamo Kiev 0-1 Benfica (Eduardo Salvio)

This has been a positive start from City, who have lost all four of their previous matches against tonight's opponents.

Ter Stegen has to be alert to cut out Sterling's low cross with De Bruyne lurking.

As expected, De Bruyne is operating centrally for City in the absence of Aguero. Mascherano has begun on the right-hand side of a Barcelona back four, with Umtiti partnering Pique in the middle.

Suarez heads clear an early corner from the boot of David Silva. Some typically risky passing across the back from the hosts in the opening few minutes.

No shortage of empty seats at Arsenal tonight, as my colleague Nick Howson reports:

Home fans asked to pay upwards of £56 for tonight's game. I can confirm that many, many thousands have decided not to bother. Good on them.

Serbian referee Milorad Mazic blows his whistle and the evening's glamour tie is finally off and running. City are kicking from right to left in this first half, decked out in that, erm, *interesting* orange and blue third strip.

Proceedings are underway at the Emirates, although things look to be running a little behind schedule in Barcelona. Former teammates Guardiola and Enrique share a moment in the tunnel.

Guardiola is not the only member of this City contingent making their return to Barcelona tonight. Maverick Chilean goalkeeper Claudio Bravo won back-to-back La Liga titles with the Blaugrana before joining City as a replacement for the unfancied Joe Hart this summer in a £17.1m deal.

It's interesting to note that the 33-year-old never made a home Champions League appearance at the Nou Camp, with Barcelona tending to prefer Marc-Andre ter Stegen in Europe.

IBTimes UK sport editor Nick Howson at the Emirates Stadium:

The atmosphere around Champions League matches at the Emirates has often been toxic, with the home side either reeling from a damaging league defeat, anticipating an embarrassing evening in Europe or facing the wrath of the north London faithful over a lengthy injury list or a listless summer transfer window.

But there is certainly some tranquility in the air tonight, perhaps helped by the calibre of the opponents, but equally by a sequence of six straight wins and an unbeaten run that stretches back to the opening day of the campaign. Surely, even Arsenal can't disrupt that feeling of goodwill, can they?

It's now being mentioned by reporters at the Nou Camp that Aguero is not currently warming up with City's six other substitutes. It will be interesting to see what a brave Guardiola says about his absence after the game.

Over in north London, Wenger makes four alterations from the side that held on to beat Bob Bradley's Swansea 3-2 despite a controversial late red card shown to Granit Xhaka.

David Ospina, Arsenal's first-choice goalkeeper in Europe, replaces Petr Cech and Kieran Gibbs is preferred to Nacho Monreal at left-back.

Xhaka makes way for Francis Coquelin, who claims he is now back to 100% after a knee injury, and Alex Oxlade-Chamberlain is given the nod ahead of Alex Iwobi.

No such surprises from Enrique, who does indeed restore Messi and Andres Iniesta to their rightful places.

Jordi Alba returns at the expense of Lucas Digne, although Javier Mascherano looks set to feature at right-back with Sergi Roberto still out and Aleix Vidal not involved. Samuel Umtiti also comes into the defence in place of Jeremy Mathieu.

Rafinha and Arda Turan are relegated to the bench.

So with Aguero surprisingly left out of the starting lineup, it appears that De Bruyne will be entrusted to lead the line for City tonight. Presumably he will operate as a false nine, flanked on either side by Nolito and Raheem Sterling.

Guardiola's side shows three changes from that aforementioned draw with Everton, as Pablo Zabaleta, Aleksandar Kolarov and Nolito all come in. Gael Clichy and Leroy Sane both drop to the bench, while Kelechi Iheanacho is omitted from the matchday squad altogether.

Kompany also fails to make the bench. Surely not another injury setback?

IBTimes UK sport editor Nick Howson at the Emirates Stadium:

No doubt that events in north London are being overshadowed by those at the Nou Camp tonight, but that might be just how Arsenal want it. The Gunners have floundered in matches against inferior opposition in recent years but without the heat of the Champions League spotlight upon them they will be hoping to put one foot in the knock-out stage.

Ludogorets without doubt represent the fairytale story of European football. Formed just 15 years ago, they are already five-time Bulgarian champions and are playing in the Champions League group stage for just the second time in their history. They only have a solitary point to show from their opening two group games but Arsene Wenger would underestimate tonight's visitors at his peril.

Arsenal vs Ludogorets

Arsenal: Ospina, Bellerin, Koscielny, Mustafi, Gibbs, Coquelin, Cazorla, Walcott, Ozil, Oxlade-Chamberlain, Sanchez

Subs: Cech, Gabriel, Elneny, Monreal, Xhaka, Iwobi, Lucas

Ludogorets: Stoyanov, Minev, Moti, Palomino, Natanael, Dyakov, Anicet, Wanderson, Marcelinho, Misidjan, Cafu

Subs: Borjan, Cicinho, Sasha, Quixada, Keseru, Plastun, Lukoki

Barcelona vs Manchester City

Barcelona XI: Ter Stegen, Pique, Alba, Umtiti, Mascherano, Sergio, Rakitic, Iniesta, Messi, Suarez, Neymar

Subs: Masip, Mathieu, Digne, Turan, Rafinha, Gomes, Paco Alcacer

Manchester City XI: Bravo, Zabaleta, Otamendi, Stones, Kolarov, Fernandinho, Gundogan, Silva, Sterling, Nolito, De Bruyne

Subs: Caballero, Fernando, Maffeo, Clichy, Sane, Navas, Aguero

BREAKING: Guardiola opts to leave Sergio Aguero on the bench

Apologies for that delay. We were experiencing one or two technical issues here at IBT Towers that have now been rectified.

Team news on the way....

As for Barcelona, who currently occupy the unfamiliar position of fourth in La Liga after taking 16 points from their first eight matches, Luis Enrique welcomes Spanish full-back duo Sergi Roberto and Jordi Alba back to the fold for the visit of City.

Lionel Messi will start alongside 'MSN' colleagues Luis Suarez and Neymar after marking his return from a groin problem by scoring shortly after replacing Sergio Busquets in last weekend's 4-0 rout of Deportivo, although goalkeeper Jasper Cillessen is still absent after sustaining ankle ligament damage in training last week.

We are expecting team news from tonight's key contests to filter through shortly, but first let's run through some injury lines.

Thankfully for Guardiola, Premier League leaders City have no new fitness worries to contend with and only right-back Bacary Sagna (hamstring) and midfielder Fabian Delph (muscle problem) remain absent from their 21-man travelling squad.

Kevin De Bruyne made his return from hamstring trouble during Saturday's frustrating 1-1 draw with Everton, while injury-plagued captain Vincent Kompany came through his very late cameo in that same match unscathed.

Sergio Aguero is expected to start after suffering a calf scare on international duty and also missing another penalty against the Toffees. Youngsters Angus Gunn and Pablo Maffeo also make the trip.

Good evening and a very warm welcome to IBTimes UK's latest live coverage of Champions League matchday three.

In-form Arsenal go in search of a seventh consecutive victory across all competitions against Bulgarian champions Ludogorets this evening, while Brendan Rodgers' Celtic will once again try to harness that incredible Parkhead atmosphere against Bundesliga outfit Borussia Monchengladbach in Glasgow.

However, there is no doubt which of tonight's eight fixtures really captures the imagination. Our feature game comes from Catalonia, where Barcelona icon Pep Guardiola returns to the Nou Camp with Manchester City in a potentially terrific Group C clash.

Stay tuned for match previews, breaking team news and confirmed line-ups ahead of what should be a belting evening of European football.