By Amalie Benjamin, Globe Staff

GREENBURGH, N.Y. – There has been a lot of talk around Knicks camp about J.R. Smith's maturity, about how he has moved beyond some of the issues he had earlier in his career. At least that was the narrative when Smith won the NBA's Sixth Man Award eight days ago.

That talk changed in the wake of Smith's suspension for Game 4 of this first-round series, a game the Celtics won Sunday to extend the series. Smith was suspended for elbowing Jason Terry in Game 3, and his maturity again was questioned.

Then there was this exchange with reporters Tuesday after Knicks practice.

Smith was asked about the Game 4 performance of Terry (18 points, including 9 in overtime). His response?

“Who?” Smith said. “I don’t even know who that is.”

It didn’t stop there.

Asked another question about Terry, Smith kept up the charade.

“Who?” he said again. “Who is that?”

And so, with the Knicks up, 3-1, in the series, there has been another shot of adrenaline for Boston, courtesy of a player who seems completely confident in his own abilities and his own effect on the series.

Asked what would have happened had he been on the court for Game 4, Smith said, “Oh, yeah. It would have been over. I would have been playing golf today.”