Arsenal are top of Group F in the Champions League.
For most of the night in France, the Gunners huffed and puffed without finding any real opportunity in a dull encounter with Marseille.
Their efforts looked to go unrewarded by three points until substitute Aaron Ramsey struck home a sensational winner with only seconds left.
The victory – which saw Arsenal’s first away clean-sheet in European competition since 2008’s 2-0 win in Milan – sends the Gunners top of their pile with 7 points.
Arsene Wenger, back in the dug-out after a two match European ban, recalled Andrey Arshavin and Andre Santos to the starting team. Aaron Ramsey, meanwhile, was deemed only fit enough for a place among the substitutes after hamstring trouble.
Loic Remy started in attack for Marseille, with Andre-Pierre Gignac on the bench after making his return from a groin injury at the weekend. With four minutes gone Alex Song mis-controlled the ball under pressure from Loic Remy, who briefly looked as though he would have a clear run on goal. A foul from Song stopped him in his tracks and the subsequent yellow card was a price worth paying.
Marseille still a dangerous free-kick to show for the error, but Mathieu Valbuena handed Wojciech Szczesny a simple save. Arsenal put together a nice move in the 10th minute, Song, Mikel Arteta and Theo Walcott combining to offer Robin van Persie a first sight of
Benoit Cheyrou caught Arsenal off guard at a throw-in when he chipped toward goal, but his attempt continued over the crossbar. Marseille were on top and appealed for handball when a cross appeared to hit Carl Jenkinson’s arm, with the referee rejecting the claim and booking Andre Ayew for his reaction.
With 20 minutes gone Arsenal started to hit back and won a corner after a threatening run by Arteta was cut short by Nicolas N’Koulou’s challenge. Arteta’s delivery from the left found Van Persie and the Dutchman’s looping header would have gone in were it not for Diawara, who was in position to head away the danger.
The Gunners had visibly raised their game, with Walcott and Arshavin beginning to get see more of the ball after quiet starts, but a quick counter-attack nearly gave the hosts a 31st-minute lead.
Remy skipped past Per Mertesacker on the byline and shaped to cut in on goal, only for the covering Jenkinson to get a deflection on a shot that squirmed wide of the far post.
Marseilles had other chances to break the deadlock before half-time, Laurent Koscielny making a last-ditch tackle on Remy and Gonzalez diverting Valbuena’s cross just off target from close range. Santos, booked earlier for a body check, was fortunate to avoid a second yellow card just before the break when he needlessly handled.
Arsenal looked to feed the ball wide to Arshavin as the second half got under way, but he was having little luck getting past Marseille right-back Cesar Azpilicueta.
It took a clever exchange of passes with Santos for the Russian to finally get away down the left but there was little support and the best he could manage was a tame centre.
Arsenal’s back line made a meal of clearing Remy’s 57th-minute cross, Jenkinson, Mertesacker and Song all trying — and failing — to get the ball away. Gonzalez and Ayew were both hustling but neither had a clear shot on goal before Jenkinson finally launched upfield. It was his last act before being replaced by Johan Djourou in some discomfort.
With 63 minutes gone, the quiet Walcott caught N’Koulou in possession inside the penalty area but could not beat Steve Mandanda at his near post. The England winger, short of inspiration and service, made way for Gervinho soon after.
The match looked to be petering out until deep into stoppage time when Djourou’s cross from the right found Gervinho who teed up an unmarked Aaron Ramsey and the Welshman smashed home a low effort past the goalkeeper for a winner.