Amare Stoudemire out Friday

GREENBURGH, N.Y. -- Amare Stoudemire's sprained ankle is a more serious injury than the Knicks first believed, and he missed Friday night's 116-93 win against the New Jersey Nets and may miss New York's game Sunday in Indiana, too.

"Looking at the replays, it's a little bit worse than what we thought," coach Mike D'Antoni said after the team's morning shootaround Friday. "But again, he played on it, and he's fine. Just a little swollen, and he'll have a chance on Sunday. But if not, then probably Tuesday [vs. Chicago] or Wednesday [at Boston]."

Chauncey Billups (bruised thigh) took part in the morning shootaround and was in the starting lineup alongside Landry Fields, Shelden Williams, Shawne Williams and Carmelo Anthony.

The Nets were without Deron Williams, who will undergo surgery Monday in Manhattan to remove bone particles and scar tissue from his right wrist. Kris Humphries (bruised heel, sprained ankle) also sat out for the Nets.

Stoudemire injured his left ankle Wednesday night when he landed on the foot of Philadelphia's Thaddeus Young while challenging a breakaway in the fourth quarter of the Knicks' 97-92 victory over the 76ers.

This was only the second game Stoudemire has missed all season, both against the Nets in Newark.

"He would have probably played if it wasn't [swollen]. But we just want to make sure he's 100 percent. He's not right now, but he will be in a couple days," D'Antoni said. "Maybe three or four days. We'll be cautious Sunday. If it's perfect, then he'll play. If not, then we'll wait another two days."

The Knicks currently sit in sixth place in the Eastern Conference with a half-game lead over the 76ers. Their first-round playoff opponent will be either the Celtics or Miami Heat.

Chris Sheridan covers the NBA for ESPN.com and ESPNNewYork.com.