NEWPORT, R.I. Boston Celtics coach Doc Rivers canceled training camp practice scheduled for today, saying he wants to give the defending NBA champions a day off before they prepare for their first preseason game.

Boston takes on the Philadelphia 76ers on Wednesday at the University of Massachusetts' campus in Amherst.

Rivers says he was pleasantly surprised by what he has seen of rookie Billy Walker.

“He's not your typical rookie that thinks he's got it figured out already,” Rivers said. “He really isn't. He knows he has some catching up to do but he's been a pleasant surprise.”

The 6-foot-6, 220-pound Walker was the 46th overall pick by Washington in the 2008 NBA draft but was acquired by Boston in a straight cash deal.

He averaged 15.3 points in just 37 career games at Kansas State and played only six during the 2006-07 season after tearing his left anterior cruciate ligament.

“Clearly, he would have gone earlier if he projected healthy,” Rivers said. “I think he would have been mid-first (round) definitely to low-first. But everyone was scared about his knee.”

Elsewhere

DENVER: One NBA general manager said the Nuggets were interested in trading for Pacers guard Jamaal Tinsley but his hefty contract ultimately kept the deal from happening. Tinsley, who has been barred from Pacers training camp because of off-court issues, is making $6.75 million this season and has three years and $21.45 million left on his contract.

NEW ORLEANS: Hornets center Tyson Chandler sprained his right ankle in the first quarter of New Orleans' preseason opener against the Golden State Warriors on Sunday.

BIG TALKERS: An NBA source said the consensus among the league's referees is that the player and coach who give them the hardest time verbally are Boston's Kevin Garnett and Utah's Jerry Sloan. The source also said the referees take into account that it's just part of their makeup and they have learned not to take it personally.

OUTDOOR GAME: The Suns and Nuggets will play the first outdoor NBA game of the modern era Saturday, a preseason contest at the Indian Wells Tennis Garden in Indian Wells, Calif., televised by TNT.

The 16,000-seat stadium is an NBA-style arena with no roof in the desert.