CELTICS NOTEBOOK - Rookie Davis looks like vet

WALTHAM - Lest there be any doubt about whether he’s serious about playing pro basketball, Glen Davis seemed to make his statement Saturday at New Jersey.

After two cameo appearances, ‘‘Big Baby’’ was given 17 minutes of playing time thanks to the absences of Brian Scalabrine and James Posey. He made the most of the opportunity.

‘‘I’m just trying to help my team as much as possible,’’ he said two days after scoring six points and grabbing eight rebounds. ‘‘Whatever the team needs me to do, whatever the coaches need me to do, I’m there to do it.’’

If there were any doubts about whether this 6-9, 289-pound rookie can play, they may have been allayed.

‘‘Not having Posey and Scal the other night, Big Baby was humongous,’’ said Celts coach Doc Rivers, who immediately laughed at an unintended pun. ‘‘He had a heckuva game for us. He did.’’

‘‘As a competitor,’’ Glen Davis said, ‘‘you want to do better. You’re your biggest critic, but I think my first time being out there (for an extended prime time appearance), I think I did an OK job. You always try to be perfect, play that perfect game but I’m just working harder and harder each day, trying to get better each day to try to put my team in a better situation to win.

‘‘I’ve got tons and tons to learn. When you’re out there with that first group it’s a whole different atmosphere. The veterans know what they’re doing. Everything is on point and being a rookie, getting thrown out there, you have to adjust. You have to adjust to the same tempo that they’re playing, you have to be alert, the antenna has to be up because you never know what’s gonna happen. But you can’t look at it like that. You’ve gotta play. Doesn’t matter if you’re a rookie. You’ve gotta play like you’ve been out there forever.’’

The Celtics are taking the inconsistent Pacers seriously, despite the fact that they’re 3-3, with three straight losses. The Pacers have failed to score 90 points three times, yet also reached 119 and 121 points in two of their wins.

‘‘I think Jim (former Celtics coach O’Brien) has them playing free,’’ Rivers said. ‘‘They really are. He’s done a nice job. They’re pushing the ball up the floor. Jim’s a big fan of the 3-point shot and they’re taking them (45-for-131). And he has the personnel, too. I’ve heard people say Jim likes 3’s; well everybody likes three when you’ve got (Mike) Dunleavy shooting them (8-for-17), and Troy Murphy shooting them (7-for-17). I’d like them, too. I think he’s done a nice job of making sure they feel comfortable shooting them when they’re open.’’

‘‘You expect that with O’Brien back at the helm,’’ said Pierce, one of two remaining Celtics to play under O’Brien, from 2001-04. ‘‘He does a lot of that on the offensive end. It’s going to be a challenge. We really have to focus on the defensive end. I’d watched them a few games. They’re putting up a lot of points. You know they’re going to defend, but the tempo surprised me, how they’re trying to get the ball upcourt to score fast, trying to get a 100-point game. They try to get easy points. If we can stop them from doing that and grind it out on defense, we have a chance of winning.’’

The Series

This is the first matchup of the season between the clubs. The Celts lost three of four to the Pacers last season. It would be easy to say that the Pacers have a great familiarity with the Celtics, starting with O’Brien, but Pierce, and Kendrick Perkins remain as his only former players. Meanwhile, the Pacers are a new team, also, featuring Dunleavy and Murphy, newcomers from last season’s trade with Golden State.

In the spotlight

Kevin Garnett, the reigning Eastern Conference Player of the Weeks, Pierce and Ray Allen remain under a microscope, having averaged 39.8, 38.4 and 40.6 minutes respectively, figures that don’t alarm Rivers. ‘‘If you wear down playing 38 minutes a night then the whole league is going to be worn down,’’ he said. ‘‘I don’t know what star’s not playing 38, 36 minutes. If we can keep it in that area I’m fine. Kevin’s the only guy you worry about minutes. But we’ve had injuries and it may increase our minutes to get through this stretch, and then as guys come back hopefully you can bring their minutes back down.’’

O’Brien replaced Rick Pitino in January, 2001, finished that season at 24-24 and compiled an overall 139-119 record with the Celts. He eventually left when he disagreed with several trades that Director of Operations Danny Ainge made, robbing the team of its defensive presence, which is an O’Brien trademark.

The Pacers revamped last January, sending Al Harrington, Stephen Jackson, Sarunas Jasikevicius and Josh Powell for Ike Diogu, Dunleavy, Keith McLeod and Murphy. Remaining are key players Jermaine O’Neal, Jamaal Tinsley and Danny Granger.