Weiss reported the forward, who previously left the bubble with the setback he suffered in Game 1 of the first round against the Philadelphia 76ers, is "progressing toward" a return and was "feeling good in Wednesday’s post-practice workout."
The plan is for Hayward to test the injury during on-court work Friday and see how it reacts.
The Butler product averaged 17.5 points, 6.7 rebounds and 4.1 assists per game during the regular season while shooting 50.0 percent from the field and 38.3 percent from three-point range.
He is someone who can take advantage of openings created when opposing defenses collapse on Kemba Walker, Jayson Tatum and Jaylen Brown, which was missing at times as Boston missed 27 three-pointers in Game 1 and another 18 in Game 2.
Having another secondary scorer who can both shoot from the outside and create off the bounce would help the Celtics deal with Miami's matchup zone.
The Heat switched to a zone for stretches in the second half of Thursday's game, and Boston struggled to create open looks. As a result, Miami seized control of the game by outsourcing the Celtics 37-17 in the third quarter alone.
Hayward would also have an extra day to recover after Game 3 since Game 4 is not scheduled until Wednesday.