“Also, a lot of reps with the medicine ball,” he said. “But it was (C’s assistant coach) Cliff (Ray), pretty much everybody. It’s a big difference. (The extra dribble) gives a guy a chance to strip the ball and even foul me a lot more. I’ll take the quick two any day.”

Lately, it’s helped him to essentially not miss. Perkins is among the NBA leaders at 64 percent from the floor this season and is shooting a ridiculous 73.5 percent during the Cetlics’ 11-game winning streak heading into tonight’s game against the Sixers. The player who many judged would never be more than a defensive thug in the paint has turned into one of the most efficient big men in the league.

“One thing I learned is not to chase the ball looking for post-ups all the time,” he said. “With Doc’s offense, usually the guy who sets the pick and rolls is the guy who’s open. So, in his offense, the screen is always open. It helps that they trap Paul (Pierce) and they trap Ray. So I am always the guy who’s left open. Then I am going to get a few easy baskets off of Rajon (Rondo) too.”

Learning to stay within his role has long been a work-in-progress for Perkins. Somewhere inside the 6-foot-10, 280-pound frame, he knew what he was. But like any young player, he thought he could be something more. Rivers said it was hard for Perkins to take a backseat offensively to Al Jefferson all the time because of their relative age three years ago. When Kevin Garnett arrived, it helped redefine the roles. But even in the last two years, Perkins would occasionally go off script and start calling for the ball on isolations when he was feeling it.

The 2-foot layup would become a 10-foot turnaround. The roll to the basket would become a double-fake and fall-away. Then he would dribble. Then he’d have problems.

But this year, Perkins has shown remarkable restraint. And it has led to some remarkable play.

“Each year, he’s gotten better,” Rivers said. “I think he’s there now. Even though there are nights he might step out of it a bit, he always gets back in it now. Now I think his goal is to be perfect at it. You can be an All-Star if you can perfect your role.”

Indeed, if anything, the improvement Perkins has shown gives him a glimpse at how much further the 12-point, 7.5-rebound performer this season thinks he can still go.

“I’m not satisfied,” he said. “I think I should take my 7.5 rebounds and probably be averaging 10 about now. I have a little under two blocks. I probably should be averaging close to three. I think there’s still room for improvement. I expect more out of myself. I think I can do better than what I’m doing right now.”

An impressive declaration considering how far Perkins has already come.

(Scott Souza is a staff writer for the MetroWest Daily News. His coverage can be found at www.metrowestdailynews.com. For updates and analysis, check out the “Courtside View” blog at blogs.wickedlocal/Celtics/.)