Julian Alvarez shone as Manchester City came from behind to begin their Champions League defence with a comfortable 3-1 win over Red Star Belgrade.

The treble winners were stunned when the Serbian champions claimed a shock lead against the run of play through Osman Bukari just before half-time in Tuesday's Group G clash at the Etihad Stadium.

Alvarez levelled quickly after the break and was then responsible for City taking the lead as his free-kick was punched into goal by the otherwise excellent Red Star goalkeeper Omri Glazer.

Rodri, matchwinner against Inter Milan in last season's final, then wrapped up a thoroughly deserved victory with a typically composed finish 17 minutes from time.

Prior to taking the lead, City had completely dominated the game, with Glazer producing a series of fine saves to thwart the hosts and Erling Haaland hitting the crossbar.

The hosts finally started to take their chances in the second period but could have scored plenty more with Kyle Walker having an effort disallowed, Haaland again hitting the woodwork and Alvarez finding the side-netting.

Red Star boast plenty of European pedigree as winners of the competition in 1991 but, facing the continent's present pre-eminent force, they were completely outplayed.

City had their first chance after nine minutes when Phil Foden had an effort deflected over and Rodri then jinked into the area before testing Glazer.

It was the start of a busy half for the Israeli keeper, who also denied Alvarez twice and kept out a point-blank header from Foden.

He could do little about City's best chance of the opening period as Haaland met a floated Foden cross with a firm header but the bar came to his aid.

Haaland had another good chance to put City ahead but turned over from in front of goal.

City were made to rue their wasted chances as Red Star, who had looked to counter-attack when possible, grabbed a shock lead on the stroke of half-time.

The hosts were punished for playing a high line as Bukari was played through by Mirko Ivanic and slotted coolly past Ederson.

It initially looked like an offside flag might spare City but the goal was awarded following a VAR review.

City, who brought on Jeremy Doku for Bernardo Silva in the closing moments of the first half, quickly regrouped and equalised two minutes after the interval.

Alvarez finished superbly after being played in by Haaland, cleverly dinking over Glazer.

Walker thought he had put City ahead moments later only to be ruled offside.

City claimed the lead just before the hour as Alvarez curled a free-kick from the left into the box. Glazer came out to punch but failed to make clean contact and the ball flew in after skimming the back his hand.

Haaland went close again when he headed against a post before Alvarez lashed just wide.

City finally gave the scoreline a more realistic look when Rodri claimed their third.

The Spaniard turned Vladimir Lucic outside the area after good work by Foden and strode forward to pass the ball into the far bottom corner.

Julian Alvarez shines as Man City start Champions League title defence with victory