Arsene Wenger lauded the sang-froid of match-winner Aaron Ramsey after the substitute gave Arsenal a precious Champions League victory with an injury-time winner at Marseille. Ramsey\'s goal, two minutes into injury time, came at the end of a dreary encounter that had been drifting towards a goalless draw that would have kept OM two points clear of the Gunners ahead of the return fixture on November 1. However, the Wales captain\'s composed finish from Gervinho\'s flick means Arsenal now lead Group F by a point and are on course to reach the last 16 for a 12th successive season. \"It was a great goal,\" said Wenger. \"When you see Aaron Ramsey in front of goal, you know you have a chance of scoring because he\'s a real goalscorer.\" Ramsey has been a regular starter in an Arsenal team traumatised by a bleak opening to the season, which has seen them annihilated 8-2 at Manchester United and restricted to just three wins in the league. Injuries, suspensions and the sales of Cesc Fabregas and Samir Nasri have obliged Wenger to rely on the 20-year-old and Wenger said he was keen to avoid over-burdening his player. \"I don\'t want to overplay him,\" said the Arsenal coach. \"He was injured for a year (in 2010), and Jack Wilshere played a lot last year (in Ramsey\'s place). I try to be more cautious when I can.\" Arsenal have now won five of their last six games but Wenger was careful not to play up the significance of Wednesday\'s result when it was put to him that it could be the match to spark their season into life. \"It\'s a little step forward but we have to stay humble because we\'re a team that has to continue to grow,\" he said. \"The next game against Marseille will be very important. \"If you look back at the last five or six games, you will see that we had only one defeat, so we are slowly getting there and that will help tonight.\" The final whistle drew a torrent of jeers from the OM fans inside a Stade Velodrome rendered half-empty by ongoing renovation work. Marseille had impressed in a 3-0 defeat of Borussia Dortmund in their previous outing but have also begun their domestic season in disastrous fashion and Wenger said he sympathised with the losing side. \"We lost two points in Dortmund in the last minutes of the game and we lost the Champions League final to Barcelona (in 2006) in the last moments too.  \"When you play against good opponents, that\'s when they take their chances.\" Marseille coach Didier Deschamps was critical of Slovenian referee Damir Skomina\'s failure to award his side a first-half penalty for an apparent handball by Arsenal right-back Carl Jenkinson. \"Taking a point would have been a good result, even though I haven\'t forgotten that there was a blatant penalty in the first half that the referee didn\'t see,\" he said. \"I was enraged by the goal, but I\'ve calmed down a little bit. You have to put everything into it but you can\'t let things get too stretched at the end of the match.  \"There, he (Ramsey) found himself completely alone and he had all the time to control the ball and shoot.\" With Marseille already 11 points outside the Champions League places in Ligue 1, Deschamps must now re-focus his players for Saturday\'s visit of promoted Ajaccio. \"There\'s work to do and we\'ll have to get it (the defeat) out of our system,\" he said. \"Of course it was an important match, but we have another very important match on Saturday. We\'ll have our backs to the wall.\"