Arfa and Yohan Cabaye, who can really hurt you.
"But we went there with the right mindset and defended well. We had great shape and got two early goals. It was probably one of our best defensive performances of the season."
Sir Alex will hope the Reds' displays improve further following the return of Nemanja Vidic. The Serbian centre-back started his first game in more than three months at Swansea.
Evans partnered Vidic at the Liberty Stadium and has been one of United's most consistent players this season. But the Northern Irishman concedes the captain's return could cost him his place in the side.
"It's healthy for the manager and the squad to have Nemanja back," he said. "If you manage to keep the captain out of the team, so be it. But if the manager wants to play Nemanja Vidic you can't really complain at that.
"You just have to be the best player you can be and if the manager picks you at the weekend you accept that. If he doesn't, you accept that too."
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