Smith was benched for Tuesday's loss to the Charlotte Bobcats.
"I need J.R. every game, every game I need J.R.," Knicks coach Mike Woodson said after the team's shootaround Thursday morning, according to reports. "And J.R. will be back in uniform today, and we'll go from there."
Smith had been benched for two of the Knicks' past four games. Woodson hasn't publicly disclosed his reasons for benching Smith.
Smith was late to a team meeting Tuesday, sources told ESPNNewYork.com, which may have led to his benching Tuesday against the Bobcats.
He also had a run-in with Woodson on Monday after he complained about his playing time in overtime of the Knicks' win over the Phoenix Suns, sources confirmed. Sources said Smith expressed his frustration with Woodson during the game and the two had a brief, heated discussion over Smith's displeasure shortly after the game.
Smith's tardiness Tuesday and frustration with playing just 45 seconds in overtime likely led Woodson to bench Smith against Charlotte.
After Thursday night's game, Smith was asked if he understood the reasoning behind Woodson's moves.
"Yes and no," Smith said. "I think it's a combination of some things, but we've got to work that out within the team and we'll go from there."
Woodson was asked on Thursday morning whether he'd spoken to Smith.
"There's nothing that needs to be said. I expect J.R. to be a pro and concentrate on playing basketball. That's why he's wearing a Knick uniform," Woodson said, according to reports. "It's a privilege to play in this league. You got to do all the necessary things on and off the court to be a pro in this league. I don't think any player should take it for granted. When he's in uniform, his job is to play. When he's out of uniform, his job is to concentrate on being a pro."
Information from ESPNNewYork.com's Ian Begley and The Associated Press was used in this report.