New York Knicks sixth man J.R. Smith played in the postseason with fluid in his left knee, a league source confirmed.

It is unclear whether Smith will need to undergo a procedure to drain fluid from his knee at this point, the source said.

A second source close to the player said Smith started complaining about knee pain during the Knicks' first-round series against the Celtics. However, Smith did not mention the injury or any knee pain publicly during the playoffs or use it as an excuse for his poor play. He said after the Knicks' Game 4 loss that he deserved all of the blame for the Knicks' struggles against the Indiana Pacers.

The injury appears to have impacted Smith's shooting.

The NBA's Sixth Man of the Year averaged 22 points on 48 percent shooting in the final month of the regular season but struggled with his shot in the playoffs. He averaged 14.3 points on 33 percent shooting in a disappointing postseason.