Reds striker Luis Suarez was suspended for eight matches after being found guilty of racially abusing the French defender the last time the two sides met at Anfield in a Premier League fixture on October 15.
"It wouldn't be a consideration," Phelan told BBC Radio Manchester when asked if United would think aboutnot selecting the 30-year-old.
"Patrice Evra is a football player who plays for Manchester United. If he is fit, he is considered to play like any other player.
"What has happened has happened. What has been said has been said. You are talking about a football match now and I think it will be a very good FA Cup tie."
Phelan also discussed the progress of young defender Phil Jones, who has almost instantly become a permanent fixture in the United team in a variety of positions since arriving at Old Trafford from Blackburn Rovers in the summer.
"We are quietly surprised with what Phil has contributed so far this season," Phelan said.
"What we intended to do was blood him in nicely and bring him through bit by bit. But he has hit the ground running.
"You can't stop the train from moving. Phil is definitely pushing in all positions. The thing is, teenagers have no fear. It is all brand new to them.
"And when you are fearless, you have a certain amount of time when you can make mistakes and get away with them."
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