- Raheem Sterling put City in front with a close-range finish after good work from Sane.
- Falcao's header gave Monaco an instant reply before Mbappe fired his side in front.
- Sergio Aguero equalised but Falcao immediately restored Monaco's lead with a dazzling chip.
- Aguero's stunning volley restored parity to the scoreline on 70 minutes before Stones gave City the lead for the second time from a corner.
- Sane, who was simply superb, scored the fifth after being teed up by Aguero.
- Saul Niguez gave Atletico Madrid the lead against Bayer Leverkusen with a stunning effort.
- Antoine Griezmann doubled Atletico's lead thanks to good work from Gameiro.
- Karim Bellarabi pulled one back for Bayer early in the second half, but Gameiro restored his side's two-goal advantage from the spot.
- Leverkusen halved the deficit once again through Julian Brandt, but Fernando Torres was on hand to give his boyhood club a two-goal cushion going into the second leg.
Full-time: Manchester City 5-3 Monaco
Incredible, absolutely incredible. The game had everything: wondrous attacking, woeful defending, baffling officiating and yellow cards aplenty.
It's tough to truly surmise that game, to be honest. If the second leg is half as good, we're in for a treat.
Have a good night.
Full-time: Bayer Leverkusen 2-4 Atletico Madrid
We're into stoppage time at the Etihad. Only three minutes, but don't rule out another couple of goals.
Third and final change for City as Navas replaces Sterling, who seems to be struggling with a knock.
GOAL! Bayer Leverkusen 2-4 Atletico Madrid (Torres)
Guardiola attempts to shore things up as Fernando replaces Aguero. The forward receives a standing ovation from the adoring City fans.
An incredible ball from David Silva finds Aguero, who picks his head up and finds Sane. The young German can't miss and has deserved a goal; he's been excellent today.
It was almost 5-4 straight away but Caballero denies Falcao from scoring a third with his feet. Just over five minutes left to play.
Bernardo Silva has made way for Joao Moutinho.
GOAL! Manchester City 5-3 Monaco (Sane)
Fabinho the NINTH player to be booked after fouling Sane.
Aguero has answered some critics this evening. He's just drawn a fine save from Subasic as he searches for his hat-trick goal.
Superb ball from De Bruyne is glanced into the path of Stones by Toure, and the defender cushions it home from close range. The England international has atoned for his earlier error and has given Guardiola's men the advantage.
But will it stay that way? 12 minutes to go, Monaco's Mbappe makes way for Germain.
GOAL! Manchester City 4-3 Monaco (Stones)
The referee is going to caution himself in a minute. Eight yellow cards so far, the latest going to Bernardo for a pull on De Bruyne.
Zabaleta has just been shown a yellow card for dissent after Lemar was fouled by Silva. Tensions are running high at the Etihad, and the referee has not made any friends tonight.
Aguero drags City level again with an absolutely exquisite volley from Silva's corner. The Argentine kept his eye on the ball as it evaded everybody and gave Subasic no chance. What a game this has been so far.
GOAL! Manchester City 3-3 Monaco (Aguero)
Shouts for a Manchester City penalty waved away as Sterling is nudged by Mendy. Replays show the left-back did make contact with the ball.
You guessed it, Monaco spring an immediate attack but Mbappe can only find the side netting.
Elsewhere, Leverkusen have halved the deficit once again in Germany. Two scintillating Champions League ties on show this evening.
A man reborn.
What a game we have on our hands, but what poor defending from John Stones.
Bakayoko fires a long ball into the channel for Falcao, who brushes off the challenge from Stones, composes himself and chips Caballero supremely to bag his second of the evening. The Colombian is a man reborn, but it's dreadful from City once again.
Zabaleta has come on for Fernandinho, less than half an hour to play.
GOAL! Manchester City 2-3 Monaco (Falcao)
Some excellent work from Sterling finds Aguero, whose shot is not the most powerful but manages to squirm through Subasic and into the net.
Full credit to Sterling for picking the pocket of Bakayoko and providing an excellent pass for Aguero, but Subasic will not sleep well tonight. All square.
GOAL! Manchester City 2-2 Monaco (Aguero)