By FOX Sports Staff
The Czech international has only made nine appearances for the club because of injury problems but did well for the Gunners in their 2-0 win over Bayern Munich on Wednesday.
The 32-year-old played the full 90 minutes in Germany although Arsenal came up just short of a remarkable comeback because of the away goals rule having lost the first leg 3-1 in north London.
With only a place in next season's UEFA Champions League to play for, Wenger is targetting a furious finish to their Barclays Premier League campaign if they are to make up the five point gap on fourth-placed Chelsea.
And he sees Rosicky as vital to achieving this goal.
"A big regret of my season is that Tomas Rosicky did not appear before January basically because he was out for a long time," he told Arsenal Player.
"Hopefully now he is fresh, he will help us until the end of the season to reach the top four.
"He can have a massive influence."
Meanwhile, Wenger feels that goalkeeper Lukasz Fabianski has also benefited from a confidence boosting outing in Bavaria.
The Polish international had not played a game for Arsenal in more than a year before Wednesday yet looked composed against Bayern as he denied Arjen Robben and Thomas Muller in impressive fashion.
"He played with authority. We know his talent and I'm very happy with his performance," Wenger said.
"He has changed a lot, there has been a complete mental transformation in Lukasz's attitude. He is more vocal, has more authority and mentally he absorbs the pressure of the game much better."
Arsenal are away to Capital One Cup champions Swansea next in the league.
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