A tight encounter was settled in the Gunners’ favour in the 90th minute when substitute Ramsey coolly slotted home Johan Djourou’s cross to give the Londoners a victory which moves them top of Group F.
The Arsenal boss, who threw Ramsey into the fray in the 78th minute, said he was in no doubt that the Wales midfielder would convert the opportunity after the ball fell to him.
“It was a great finish, you see Ramsey in front of goal and you know you have a good chance to score. He is a goalscorer,” said Wenger.
“I do not want to overplay him. I have seen in my mind that he had been injured for a year – Jack Wilshere played a lot last year [and is now injured]. I try to be a bit more cautious when I can.”
Wenger added: “We left it very late but we had a difficult start. We lost some balls in the first half due to the fact Marseille pressed us well.
“We’ve made a little step forward but we have to be humble. We are a team who must continue to grow and we have to show that. The next game at home against Marseille is very important.”
Marseille: Steve Mandanda, Souleymane Diawara, Nicolas N’Koulou, CÃ©sar Azpilicueta, JÃ©rÃ©my Morel, Mathieu Valbuena, Alou Diarra, Benoit Cheyrou (Charles KaborÃ©, 87), Lucho GonzÃ¡lez (Morgan Amalfitano, 73), LoÃ¯c Remy (AndrÃ©-Pierre Gignac, 69), AndrÃ© Ayew.
Arsenal: Wojciech Szczesny, Carl Jenkinson (Johan Djourou, 62), Per Mertesacker, AndrÃ© Santos, Laurent Koscielny, Theo Walcott (Gervinho, 67), Andrey Arshavin (Aaron Ramsey, 78), Mikel Arteta, Tomas Rosicky, Alexandre Song, Robin van Persie.
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