WALTHAM - Did you know that Celtics rookie point guard Gabe Pruitt almost stayed at Southern Cal because of O.J.?

No, not O.J. Simpson. Rather, former high school phenom O.J. Mayo, who will be a freshman with the Trojans this season. But while playing with O.J. Mayo at USC was intriguing to him, Pruitt is ecstatic to be playing with Kevin Garnett, Ray Allen, and Paul Pierce with the Celtics instead.

"I did consider staying at school for another year to play with O.J. and to build off what we have," said the 21-year-old Pruitt. "But at the last minute I decided to go on.

"There are no regrets. There are not a lot of people that are going to get a chance to play with three All-Stars and a team that most people consider is going to win a championship."

O.J. Mayo was arguably the best high school player in the country last season, and definitely the most hyped. Pruitt was one of his hosts when the McDonald's All-American surprisingly decided to visit USC. The guards became instant friends and still keep in touch.

But since Pruitt was uncertain about whether O.J. Mayo was going to be a Trojan, he left for the NBA before O.J. Mayo committed in writing. Pruitt averaged 12.5 points and 4.3 assists as a junior last season, earning All-Pac-10 honorable mention honors.

"I was expecting [O.J. Mayo] to come in kind of arrogant," Pruitt said. "He's actually real down to earth and humble. The way he loves the game of basketball is something I respect. He's actually a gym rat. He loves the game. He's in the gym all the time.

"He called me when I was in LA before the draft. He'd say, 'Where are we playing today. I'm trying to go to the gym.' After we started playing a couple times, we developed a relationship."

Pruitt was projected as high as the No. 3 point guard and a mid-first-rounder in the draft. The 6-foot-4-inch, 170-pounder, his parents, and his agent went to New York to watch the draft in person. Pruitt's name, however, wasn't called until after six point guards were selected. Boston tabbed him in the second round with the 32d overall pick.

"I thought I was a first-round pick," Pruitt said. "I heard a lot of things and knew pretty much anything could happen. You never know. Nothing's set in stone.

"After a while I was just sitting there saying, 'I just want my name to be called.' If I get on a team and hear my name called, I'll make the rest happen. It was real nerve-racking, but at the end I ran into a great situation."

Celtics director of basketball operations Danny Ainge was surprised Pruitt was available at No. 32.

"I just liked his talent," Ainge said. "He has a gear on both ends of the court. He kind of moves and glides. I felt with confidence and a little more focus on the game, his shot, his abilities; he has a chance to be a really good player."

Pruitt has averaged 4.7 points, 1.3 assists, and 10 minutes per game in the exhibition season. Coach Doc Rivers played him late in the first quarter of Wednesday's 101-61 win over New York. Although Rivers said Pruitt was nervous, he finished with 13 points on 6-of-9 shooting, nailed a 3-pointer, and had four assists in 17 minutes. Rivers feels Pruitt has a lot to improve on, most notably running the offense, and "hopes but doesn't know" if he can be a rotation player this season.

"He has potential," Rivers said. "He's not a point guard yet. But he's going to be a point guard, and a very good one. But he's not there. He needs work. But that's OK and we're fine with that. He wants to learn. He works hard every day in practice. He's not playing with the better players most of the time, which doesn't help. So, he didn't have that advantage.

"If you get Gabe and you put him in with Kevin Garnett, Paul, and Ray, that makes it easier for him. But he's not playing with those guys, so that makes it tougher for him. He still just has to learn how to run a team under pressure."

Boston plays New Jersey tonight in an exhibition in Worcester. Celtics guard Tony Allen practiced yesterday despite blurry vision from a recent eye injury and is expected to play after missing Wednesday's game.

"Basically, I'm just trying to get something going," Allen said. "These minor injuries, I've just got to fight through them."