The midfielder has been out of action since the opening day of the season after suffering a knee injury against Aston Villa.
He can make absolutely a great impact for any team in the world so we are really pleased that he’s back
However, the England international played 45 minutes for Arsenal’s Under-21 side on Thursday and is set to return to first-team action for Monday’s trip to Aston Villa.
And following the news that Theo Walcott has been ruled out for the rest of the season, Mertesacker stressed the importance of getting the likes of Oxlade-Chamberlain back to top form.
“We need every single player and in particular Alex,” Oxlade-Chamberlain told Arsenal Player. “It was a real shock when he was out after Aston Villa.
“Following that game we did really well as a team but we need him because he can always make the difference with his speed, with his passing and obviously with his finishing.
“He can [make] absolutely a great impact for any team in the world so we are really pleased that he’s back.
“But I think he needs some time to get through training and to have some good games, but I’m really pleased for him that he got 45 minutes against Fulham. That is a step back to absolutely full fitness.”
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