Evra was at the centre of the incident on Saturday in which Livepool striker Luis Suarez failed to shake his hand before the Premier League match at Old Trafford following the completion of his eight-match ban for racially abusing the Frenchman.
Evra was also criticised for wildly celebrating United's 2-1 victory in front of Suarez.
"It was an emotional weekend for him so I think this is the right thing to do," Ferguson told a news conference.
United striker Dimitar Berbatov and midfielder Ryan Giggs did not travel with the squad for the round-of-32 first-leg match in Amsterdam because they are injured.
Giggs will have to wait a little longer to make his 900th appearance for United.
Features and profiles on Giggs, 38, appeared in many newspapers on Wednesday in anticipation of him reaching another milestone in his long playing career.
Giggs, who made his debut for United in 1991 and has played more times for the club than anyone else, could now make his 900th appearance in the return leg against Ajax at Old Trafford next week or when United visit Norwich City in the Premier League three days later.
United have no game at the weekend after being knocked out of the FA Cup by Liverpool last month.
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