PROVIDENCE — Bill Walker has a bright NBA future.

At least that’s what Boston coach Doc Rivers thinks of the Celtics 6-foot-6, 220-pound, second round draft pick.

Considered the third best high school player in the country in 2006, Walker’s freshman season at Kansas State was cut short when he ruptured the anterior cruciate ligament in his left knee in a game against Texas A&M on Jan. 6, 2007, which required surgery.

It was the second time he had knee surgery, the first coming in 2003 on his right knee. Last year Walker averaged 16.1 points and 6.3 rebounds with Kansas State, and many people thought that he would be a lottery pick.

But he suffered a third knee injury during a workout with the Golden State Warriors on June 15, 2008, and fell to the second round, 47th overall, to the Washington Wizards, who traded Walker to the Celtics for cash.

Since joining the Celtics, Walker has been working out with strength and conditioning coach Bryan Doo on landing properly after jumps to try to prevent another knee injury.

Walker says that both of his knees are feeling “great,” and that he is as explosive as he was two years ago.

Rivers said that because Walker has had to fight to overcome adversity throughout his basketball career, he believes Walker has what it takes not only physically, but more importantly, mentally, to have an outstanding career in the NBA.

“What I love over anything about him is that he’s very competitive,” Rivers said. “Young guys think they competed in college. But they come up here and they found out it’s a whole different level of competition — not only as far as talent, but as far as inner competition.

“Billy has that level now. He’s not going to back down to anybody. He’s going to go out there and he’s going to compete against everybody. That gives him a chance to be a very good player.”

Walker had a two-handed crowd-pleasing dunk midway through the second quarter last night that cut Cleveland’s lead to 43-39 when he hammered home a missed shot by Brian Scalabrine.

James itching for a title

Cleveland superstar LeBron James said he is excited that the basketball fans of Rhode Island got a chance to see him and the Boston Celtics play last night at the Dunkin Donuts Center.

“It’s always good when you get an opportunity to play in front of fans who don’t get an opportunity to see NBA players all the time unless it’s on TV…,” James said.

Coming off a gold-medal performance with Team USA at the Olympics, James said that he is now even hungrier to win an NBA title.

“I’m motivated,” James said. “I think that this is the best chance that we’ve had since I’ve been on this team. We have every position. We have guys that can come in at every position on the court so it’s great to have this team.”

Ring presentation planned

The Celtics will open their regular season against James and the Cavs on Oct. 28 and will be given their World Championship rings that night.

“Of all the nights, that’s probably the one I’m looking forward to because the players talk about the ring,” Rivers said. “…I think that will be special in front of the home crowd. The second reason I like it is because to me that will signify the end of last year and we can move on and start focusing on [this year].”

Cassell sits out the game

Boston backup guard Sam Cassell was on the sidelines in street clothes for the game. He missed Wednesday’s game against Philadelphia and Thursday’s practice for personal reasons.

Couz is history

After 34 years as a television analyst for the Celtics, Comcast SportsNet decided to release 80-year-old Celtics legend Bob Cousy.

rlee@projo.com