He did not participate in shootaround on Wednesday.
Durant experienced some cramping during Sunday's Game 1, a 121-109 win in which Durant finished with 32 points and 10 rebounds.
Warriors coach Steve Kerr said Durant didn't practice on Tuesday, noting, "If he didn't practice, there's concern."
Durant previously missed 19 games with a strained MCL and a bone bruise in his left leg.
The Blazers will continue to be without center Jusuf Nurkic, who is recovering from a right leg fracture.