Anthony was listed as a game-time decision earlier Wednesday. He informed the team he could play a little more than an hour before tipoff.
The Knicks' star had missed the past two games because of lingering discomfort in his sprained left ankle. Anthony said Tuesday he'd be taking a cautious approach with his ankle.
"Of course, I want to play," he said. "But if I'm not able to go out there and be the player I can be and help my team, then I'm not going to step foot on the court."
After going through a few running and shooting exercises with a member of the Knicks training staff, Anthony decided he could play. Steve Novak, however, sat out with flu-like symptoms.
"I never took a fall like that," said Anthony, whose hip, back, knee and ankle were all affected. "I think I got lucky, especially after looking at the fall."
Anthony has missed four games, and the Knicks are 2-2 without him.
With Anthony sidelined because of a laceration on his left middle finger, the Knicks beat the Heat on the road by 20 points and lost to the Chicago Bulls. In Anthony's most recent absence, the Knicks beat the Cleveland Cavaliers on Saturday but lost to Jeremy Lin and the Houston Rockets on Monday.
Ian Begley is a regular contributor to ESPNNewYork.com