“Not yet,” Doc Rivers  replied quickly. “I think he’s getting close. You’ve got to execute when you’re on the floor. That’s an area he has to improve on. He’s talented, but there’s a level, to me, of intensity that you have to play with every night and focus and he’s inconsistent in that. But he’s getting there and he’s a great kid and he will get there.
“We want to use him, but he has to come get it,” Rivers continued. “We’re not going to give him anything.”
Johnson went and got it on Sunday against the Bulls and their talented — and huge — frontline. After a rough first few minutes, Johnson scored 12 points on 6-for-13 shooting and managed to hold his own on the boards. He was credited with just one block, but it seemed like he altered several other shots. Even when the likes of Omer Asik and Joakim Noah  were playing through the generously-listed 220-pounder, Johnson kept competing.
As is his custom, Rivers handed out praise judiciously to his young player.
“Yeah, but he’s got to keep doing it,” the coach said. “You know, one game doesn’t make a star. One season doesn’t make a star. So you’ve just got to keep doing it, and he’s got to do it consistently. He will, like I keep saying, he’s a great kid and he wants to do it. He’s young and he’s still learning focus and all that. But he’s a good player.”
Johnson is the latest young player on the Celtics’ roster to get his chance at making a meaningful contribution. With Brandon Bass  sidelined for up to two weeks with swelling in his knee and Jermaine O’Neal  missing the last two games with an assortment of injuries, Johnson is one of three healthy frontcourt players alongside Kevin Garnett . The others are Chris Wilcox  and Greg Stiemsma .
Johnson has patiently waited his turn while fellow Purdue rookie E’Twaun Moore  has already made an impact as a reserve guard, and second-year player Avery Bradley  has grabbed hold of the backup point guard job. Even Stiemsma, the 26-year-old veteran rookie has been ahead of the first rounder, but Johnson’s talent has been on display, albeit in only 103 minutes with most of that coming in garbage time.
With a huge small-sample size warning blaring in neon blinking lights, Johnson is shooting 55 percent and averaging 18.2 points and almost six rebounds per 36 minutes. He made 3-of-7 shots from 16-23 feet and seems comfortable taking the jumper in the halfcourt. Johnson also got out on the break and finished at the rim, including a highlight-reel alley-oop lob from Rajon Rondo  late in the fourth quarter.
Johnson’s breakout performance followed a forgettable seven-minute stint against the Raptors on Friday when he seemed hesitant and confused on the court. Rivers called two quick timeouts and let Johnson — and the rest of the team — have it. Still, without much practice time to work on his game, Johnson has drawn praise from Rivers for his mature approach.
As with the other young players, the hard part starts now. Johnson must perform consistently, night in and night out, while Bass and O’Neal are injured. One game does not a career make, but for the other rookie from Purdue, Sunday afternoon was a positive step.