MIAMI (AFP) — Jimmy Butler is battling to be fit as Miami Heat look to take a stranglehold on the playoff series against the New York Knicks at Madison Square Garden on Tuesday.

Butler, who rolled an ankle during Miami's Game 1 victory over the Knicks, is listed as questionable for Game 2 of the Eastern Conference semifinal series, Miami confirmed.

Heat coach Erik Spoelstra told reporters on Monday that Butler was undergoing intensive treatment in a bid to be fit for the game, adding that a final decision on his fitness would be left to the last minute.

"Same as last night," Spoelstra told reporters on Monday when asked about Butler's status.

"He's doing treatment around the clock. We probably won't have any update until before the game."

Any injury absence involving Butler would be a huge blow to Miami.

Butler has been in scintillating form during the postseason, producing huge performances in the first round of the playoffs as Miami stunned the top-seeded Milwaukee Bucks.

The Knicks, meanwhile, are also sweating on injuries to key players as they look to level the series on Tuesday.

Forward Julius Randle, who sat out game one on Sunday due to an ankle sprain, is again listed as questionable, as is Knicks guard Jalen Brunson, who is nursing right ankle soreness.