Traore was facing his former club on Sunday, but was forced out of the game clutching his leg.
Ajax coach Peter Bosz remarked after the 1-0 win: "I saw him grab a hamstring.
"That's why I changed him. I think it is not so bad. Maybe it was a slight sprain if he had a little cramp."
Traoré started as centre-forward and was replaced by substitute Kasper Dolberg. Ajax plays Thursday against Panathinaikos in the Champions League. Three days after that meeting in Athens awaits an away match with Heracles Almelo.