Holders Arsenal dumped out of the FA Cup by Nottingham Forest after thriller at the City Ground

Forest have done it! For the first time in under Arsene Wenger's management, Arsenal are out of the FA Cup at the third round stage. The holders fall at the first hurdle after an astonishing cup tie at the City Ground.

Full-time: Nottingham Forest 4-2 Arsenal

Walcott can't make it three! Nketiah pounces on a dreadful pass back and tries to clip the ball over Smith. It's a good attempt, but Smith does brilliantly to get a hand onto it, pushing it over himself and sending it rolling out for a corner. Walcott is racing to get onto the ball before it does that but he can only hammer into the side netting from an impossible angle.

Four minutes of injury time have been added on.

Good grief, this game has everything now. Joe Worrall is shown a second yellow card after crashing through the back of Akpom.

RED CARD - Joe Worrall

Another change for Arsenal, Chuba Akpom is on for Debuchy.

After consulting his assistant, Moss awards the goal! Dowell slipped and almost made a mess of his spot kick and Arsenal were adamant he had touched it twice as he slipped. He stuck it past Ospina anyway and the goal stands.

But wait, has it been given? Dowell slipped as he struck it, was there a double touch?

Goal! Nottingham Forest 4-2 Arsenal (Kieran Dowell, 84)

Another penalty for Forest! A dreadful ball out from the back is pounced upon by Traore who bursts forward, skipping past Mertesacker like he isn't there. Debuchy tries to stop him in the box but the foul is given and Jon Moss points to the spot!

PENALTY - Nottingham Forest

Arsenal pull one back! Welbeck races onto a ball down the inside left channel that Smith looks to have covered, racing out of goal to smother the ball. Somehow it slips through underneath him and Welbeck is there to roll the ball into an empty net.

Goal! Nottingham Forest 3-2 Arsenal (Danny Welbeck, 78)

Walcott lifts a deep ball in and there a soft appeals for a penalty that are ignored.

Arsenal now have a free kick out on the right wing that Walcott will swing in.

Forest are embarrassing Arsenal's backline at the minute. Dowell, for good reason, fancies his chances against Mertesacker and easily beats the big German before cutting a ball across goal looking Brereton. This time he isn't there waiting for it however and the Gunners clear.

Smith denies the sub Nketiah! Welbeck does brilliantly to slide a ball through for the 18-year-old, who brilliantly spins past his man but his low drive is well saved by the Forest goalkeeper.

Arsenal respond by throwing on Eddie Nketiah who replaces Willock.

And Forest have three! Brereton demands the ball and sends Ospina the wrong way. Perfect penalty.

Goal! Nottingham Forest 3-1 Arsenal (Ben Brereton, 64)

Penalty for Forest! What a nightmare for Rob Holding; he sticks out a leg that sends crashing to the turf. Easy decision.

PENALTY - Nottingham Forest

Brereton once again gets the better of Holding, scampering in front of him out on the byline and winning another free kick for his side.

The corner breaks to Lichaj who is urged to shoot by the home supporters. Understandably, he obliges, but this one isn't as accurate as his earlier effort.

Walker gets on the ball for the first time out on the left and curls a beauty of a cross into the six yard area towards Brereton. He sticks out a boot to knock it goalbound but Holding is in the way and the home side get the corner.

Nelson tries to jink his way into the box from the left but Lichaj sticks a foot in to take the ball away from him and launches it upfield. Brereton does well to hold it up, getting his body in the way and winning a free kick off Holding to give his side a much needed breather.

Here's a first change for Forest with Tyler Walker coming onto replace Clough.

It;s been a good response from Arsenal at the start of the second-half. As you might expect, they are dominating possession and are threatening to break between the Forest back line.

And we are back underway for the second-half; the holders are 45 minutes from going out of the FA Cup unless they can change things.

Half-time: Nottingham Forest 2-1 Arsenal

Lichaj does it again! What a stunning strike from the full-back. Cash bursts inside his man down the right and cuts a cross back into the box. Debuchy clears it, but only to the edge of the box where Lichaj watches it fall out of the air, takes it on his chest and loops an astounding volley into the top corner with Ospina rooted to the spot.

Goal! Nottingham Forest 2-1 Arsenal (Eric Lichaj, 43)

Play resumes and whatever Ospina has done seems to have done the trick, he cna continue.

The game stops for a moment with David Ospina needing a bit of treatment. He seems to have a problem with his finger.

Ospina denies Brereton! The Forest forward makes a terrific run in behind Mertesacker and latches onto a lofted through ball. He cuts inside onto his right, opening up his body to try and pass it into the far corner but Ospina is equal to it with Mertesacker hacking away the loose ball.

Five minutes of the first have remain.

Walcott scampers past challenges across the face of goal, looking for room to shoot but he is well marshalled by Lichaj, who defends well intercepts.

Smith denies Welbeck! Maitland-Niles slides a great ball through for the former Manchester United striker but the Forest goalkeeper gets off his line quickly to make the block. Even if he had beaten him it wouldn't have counted; the offside flag is up.

Ospina denies Forest a second! Brereton is freed down the inside right channel and chops the ball infield to take it away from Holding at the back. He fires on goal from 12 yards out but the Arsenal goalkeeper is equal to it.

Arsenal have been in control since that equaliser went in; a good response from the away side, especially from Reiss Nelson, who did brilliantly to win the free kick for his side.

Arsenal respond straight away! Walcott takes the free kick, hanging it in the air with Holding leaping to nod a downward header on goal. His effort comes back off the post, but Mertesacker is the quickest to react, chesting it down and converting on the half volley with his left foot.

Goal! Nottingham Forest 1-1 Arsenal (Per Mertesacker, 23)

Arsenal look to respond straight away with Nelson winning a free kick in a similar position from where Forest just scored from after neatly nutmegging Cash.

Forest have the lead! From that free kick, Kieran Dowell fires a vicious effort into the six yard area, over Arsenal's two man wall. That wall is what keeps Lichaj onside as he gets onto the end of the delivery, thumping his header into the roof of the net with Opsina unable to keep it out.

Goal! Nottingham Forest 0-1 Arsenal (Eric Lichaj, 19)

Forest work a short corner with Clough neatly backheeling into Cash who is pulled back right on the edge of the box by Maitland-Niles. Forest free kick.

Close from Forest! It's a superb run from Clough as he cuts in from the left with a vital deflection from Mertesacker preventing his effort from hitting the target. The ball breaks to Cash who takes a touch before hitting a low effort across goal but Ospina gets down quickly to push it around the far pot. Great save from the Arsenal goalkeeper, good stuff from Forest.

Old teammates Walcott and Armand Traore battle for the ball out near the byline with the former Gunner getting the better and is able to usher the ball out for a goal kick.

Debuchy now bursts forward, finding Walcott out on the right who swings a decent cross into Welbeck who is waiting in the middle. The former Manchester United mistimes his jump however and his header is off target.

Willock does well in his own area however, neatly moving the ball out to Nelson who threatens to counter only for Osborn to slide in and put a stop to that.

It's a neat passage from play from Forest, ending with Osborn's attempt to free Lichaj down the right deflected out for a corner.

Walcott suddenly finds himself free inside the box off to the right but can't his effort across goal isn't quite a shot and isn't quite a cross either, allowing Smith to scamper out and collect the loose ball.

Brereton provides the first test of Mertesacker's match sharpness, catching the German out as he cuts in from the left by Opsina is equal to his tame effort on the ball.

Walcott loops it in with Mertesacker up from the back but Forest manage to clear.

Forest are trying to press Arsenal as they knock the ball across the pitch in the early stages of the match but the Gunners keep hold of it under pressure, winning the first corner of the match that Walcott will take.

And the Gunners get us underway at the City Ground.

Five minutes until kick-off; here's another look at the teams taking the field.

Nottingham Forest team to face Arsenal: Smith, Lichaj, Mancienne, Traore, Osborn, Cash, Clough, Brereton, Dowell, Vaughan, Worrall

Subs: Henderson, Mills, McKay, Bouchalakis, Walker, Cummings, Vellios

Arsenal team to face Nottingham Forest: Ospina, Debuchy, Mertesacker, Holding, Nelson, Willock, Elneny, Maitland-Niles, Walcott, Iwobi, Welbeck

Subs: Macey, Chambers, Osei-Tutu, Dasilva, Reine-Adelaide, Akpom, Nketiah

There was a fairly decent example of #TwitterBants from Forest this week, lapping up news that Arsene Wenger will be among the thousands watching from the stands today.

It is starting to fill up at the City Ground; 20 minutes until kick-off.

There are just two changes for Forest meanwhile with Zach Clough and David Vaughan both coming in for Barrie McKay, who drops to the bench, and Liam Bridcutt, who misses out completely.

Daryl Murphy, who has seven goals to his name this season, misses out through injury.

It's a completely different team for Arsenal this afternoon, Arsene Wenger has made nine changes to his starting XI tonight with Rob Holding and Ainsley Maitland-Niles the only players to retain their spots.

Per Mertesacker comes in for his ninth starting appearance of the season, joined in that back three by Mathieu Debuchy. Jack Wilshere is given the afternoon off with Chris Willock and Mohamed Elneny forming the midfield two with Theo Walcott, Alex Iwobi and Danny Welbeck selected in attack.

The Arsenal team has arrived at the City Ground, Mohamed Elneny is among that party and he will start in midfield this afternoon.

Nottingham Forest team to face Arsenal: Smith, Lichaj, Mancienne, Traore, Osborn, Cash, Clough, Brereton, Dowell, Vaughan, Worrall

Subs: Henderson, Mills, McKay, Bouchalakis, Walker, Cummings, Vellios

Arsenal team to face Nottingham Forest: Ospina, Debuchy, Mertesacker, Holding, Nelson, Willock, Elneny, Maitland-Niles, Walcott, Iwobi, Welbeck

Subs: Macey, Chambers, Osei-Tutu, Dasilva, Reine-Adelaide, Akpom, Nketiah

BREAKING: Chris Willock and Mohamed Elneny start in midfield for Arsenal with Danny Welbeck selected up front.

Steve Bould will be the man on the touchline for Arsenal this afternoon with Arsene Wenger beginning a three-match ban.

Might Jack Wilshere be in line for a rest this afternoon? The England international has started and completed six of Arsenal's last seven matches having reclaimed his spot in the first-team but with that trip to Chelsea looming, Wenger might be considering it.

Ainsley Maitland-Niles, Calum Chambers and Rob Holding would usually be the names to benefit from Arsene Wenger rotating his squad for the FA Cup. All three started midweek against Chelsea however and with injuries causing problems, Maitland-Niles and Chambers may be called upon again when the Gunners travel to Stamford Bridge on Tuesday.

With that in mind, Arsene Wenger may decide to hand the pair a rest this afternoon.

The Gunners boss is limited in who he can pick this afternoon with injuries still causing havoc in his squad. Sead Kolasinac, Nacho Monreal, Aaron Ramsey, Laurent Koscielny and Olivier Giroud remain on the sidelines today. All were ruled out for Wednesday's 2-2 draw with Chelsea and none are ready to return this afternoon.

With this afternoon's fixture sandwiched between Premier League and Carabao Cup meetings with Chelsea, expect plenty of changes for Arsenal this afternoon. Wenger said this week:

I will rotate a little bit because we have also come out of a very high-loaded period. We played three big games in six days and twice we were away, followed by a big game at home.

"We have to keep our level of focus, of urgency, because the third round is very difficult especially when you play away from home against a Championship team. We play on Wednesday again, so I have to rotate a little bit.