Kylian Mbappé is an exciting talent, Pep Guardiola's gamble backfires and Monaco are genuine underdogs

Five things we learned: Monaco overcame English opposition once again in the Champions League

The Ligue 1 leaders celebrate their win over Manchester City (Getty )

Monaco fought back from a two-goal first leg deficit to beat Manchester City 3-1 and book their place in the UEFA Champions League quarter-finals at the Stade Louis II.

First half goals from Kylian Mbappe and Fabinho sent the Ligue 1 leaders on the way to overturning last week's 5-3 defeat and going through on away goals after a 6-6 aggregate draw.

City clawed back into the game in the second half with Sergio Aguero missing a number of chances before Leroy Sane put his side back in front on aggregate with close-range finish on 71 minutes.

But the visitors' revival did not last long and another defensive lapse allowed Tiemoue Bakayoko to seal a famous Monaco victory when he crashed home a header from Thomas Lemar's free-kick.

Here are five things we learned from the thrilling tie...

Monaco’s free-flowing home approach will frighten their next opponents

Monaco have made Stade Louis II an absolute fortress this season. The Ligue 1 leaders are unbeaten on home soil in their last six matches and have scored a remarkable 84 goals at home this season – almost 30 more than their domestic rivals, PSG.

Whoever gets drawn against Monaco in the quarter-finals of the Champions League will be fearful of their attacking prowess. The energy and persistence of their forward players, in particular the irrepressible Kylian Mbappé, will frighten all of the teams left in the draw. Leonardo Jardim has instilled a rock solid team spirit at the club which is somewhat similar to Leicester City’s and his team will be confident of beating whoever they draw in the next round.

Guardiola’s defensive gamble back-fired

John Stones and Aleksandar Kolarov formed City's central defensive partnership and Mbappe ran them ragged in the opening exchanges. But it would be harsh to hold the pair totally to account for City’s defensive woes. They were offered little support from their midfield, with Fernandinho the only defensive minded midfielder selected by Guardiola.

The manager boldly dropped Otamendi to call up Kolarov, who he felt would better cope with Monaco’s counter-attacking style, but that decision ultimately backfired. Kolarov was nowhere near Bakayoko for Monaco's third goal as the midfielder beat him from Thomas Lemar's free-kick to head past Willy Caballero.

Mbappé will be hot property when the transfer window reopens

The teenager was utterly superb against Manchester City (AFP/Getty)

The French forward, who was still 17 throughout the group stages of the competition, scored on his first Champions League start in the first-leg of this tie and his goal-scoring form shows no sign of stopping. He opened the scoring against Manchester City after just eight minutes and had the ball in the net for a second time shortly after, only to be flagged for offside.

The teenager has now scored 11 goals in his last 11 games and has well and truly arrived on the European stage. A number of Europe’s elite clubs are in need of a new forward this summer and, alongside the likes of Paulo Dybala and Romelu Lukaku, Mbappé will find himself in high demand come July.

Menacing Monaco need to sort out their defence

Sure, Monaco can attack with verve and menace but they have looked vulnerable at the back in their two matches against Manchester City. Djibril Sidibé and Benjamin Mendy might be two of the most talented full-backs in Europe when it comes to rampaging forward, but defensively they can prove vulnerable. 32-year-old Andrea Raggi meanwhile struggled against the pace of Leroy Sane and will likely be targeted in the quarter-finals.

The great European strike-forces will not fear this defence and the likes of Pierre-Emerick Aubameyang, Cristiano Ronaldo and Lionel Messi will all fancy their chances at the Stade Louis II. Monaco will always rely on themselves out-scoring the opposition, but that will get harder and harder as the standard of attacking players they face increases.

Aguero will fear for his long-term future at City after this performance

City spent almost all of the first half on the back foot and Sergio Aguero cut a lonely figure in the Monaco half as Raheem Sterling, Kevin De Bruyne, David Silva and Leroy Sane all dropped back to try and shore things up in midfield. In fact, City did not have a shot on goal in the entire first half for the first time ever in a Champions League game.

City shaped up better in the second half with Silva playing at the tip of a diamond behind Aguero and they created more chances as Monaco dropped their intensity. However, the Argentinian striker was unable to take any in arguably one of his worst ever performances in a City shirt.