After the formal part of practice concluded on Friday, Tyler Zeller went off to the side and worked with player development assistant Aubrey McCreary on ball-handling tricks. McCreary, himself a magician with a basketball, had Zeller transfer a miniature ball from one hand to the other while simultaneously dribbling a regulation basketball between hands. Zeller fumbled with the drill at first, but it didn't take long for him to get the hang of it, which perfectly illustrates how his rookie season is progressing. Although he shot just 2-of-10, Zeller grabbed 10 rebounds in Tuesday's win over the Boston Celtics and now has 24 in his past two games. He is averaging 11 in his past three games. Zeller still has a long way to go in both game and stature, but he has adjusted nicely since Anderson Varejao fell out of the lineup with his knee injury. Zeller is averaging 10 points and 7.6 rebounds in 17 starts, although he is shooting just 38 percent. He has also been manhandled at times by more physical centers like Dwight Howard and DeMarcus Cousins, which is why he is dedicating this summer to bulking up. "I definitely need to get tougher," Zeller said. "I think some of it is going to come as I mature and as I get stronger. Right now I'm kind of undersized for a 5 man [center]. I do what I can, but at the same time you can't really overpower too many people in this league. I've definitely got some work to do, but I don't know that I can do that work right now. I have to wait until the offseason." Nearly all players lose weight during the course of the season as a by-product of all the running. Zeller came to training camp at 248 pounds — the biggest he's ever been — but said he's down to 240. He'd like to get up near 260, but said he can't pack it on all at once or he'll lose the quickness and agility that makes him valuable now.