WALTHAM, Mass. (AP) – New coach Doc Rivers knows how he wants to change the Celtics, whether it’s through a trade, free agency or with the three first-round picks Boston has in Thursday’s NBA draft.

“We have to instigate a lot more,” Rivers said, searching for a way to challenge his team without questioning its toughness. “I think we were the team that got punched. I didn’t like that.”

Rivers was hired in April, after the Celtics’ season ended, but he didn’t report to work full-time until after completing his obligation to ABC as a TV analyst for the NBA Finals. It was there that he watched the Detroit Pistons upset the superstar-laden Los Angeles Lakers for the title.

The Pistons may not have been as rough as they were in their “Bad Boys” incarnation of the late 1980s, but no one would say they were afraid to instigate, either.

“It’s a copycat league,” Rivers said.

Rivers has been leaving a lot of the draft scouting to basketball boss Danny Ainge and his staff, instead scouting his own team. Watching last season’s Celtics games on tape, he came to the same conclusion as Ainge and many Boston fans.

“Tell you what,” Rivers said, “some bad games in there.”

The Celtics made the playoffs despite losing five of their last six games, posting a 36-46 record that was good enough for the eighth seed in the Eastern Conference. They were swept by the Indiana Pacers in the first round.

Ainge has been making over the team for a year, and the draft will only be a part of it. The Celtics have the 15th, 24th and 25th picks in the first round; the first is theirs, the second came in the deal that sent Antoine Walker to Dallas and the third for shipping Mike James to the Pistons.

Rivers and Ainge agreed that the draft is deep with talent but lacking the LeBron James-style superstar that can turn a team’s fortunes around.

“I think it’s going to be one of those drafts where, 10 years from now, there’s going to be a ton of guys still playing in the league,” Rivers said.

Scuttlebutt has Ainge interested in Robert Swift, a 7-foot high school center from Bakersfield, Calif. Ainge acknowledged the rumors but also said no one knows what he is thinking.

Ainge said his goal for the draft was to come up with another point guard to complement Marcus Banks, and to add size. He also said that everyone the team drafted should be tough.

Ainge shot down a report, published in Chicago, that he had struck a deal to send Paul Pierce to the Bulls for Tyson Chandler, the No. 3 overall pick and change.

“It’s not happening,” Ainge said.

Said Rivers: “No one’s untouchable, but Paul is as close to untouchable as you’re going to get. I would be very surprised if Paul Pierce is not in a green jersey next year and for a long time.”

Ainge also reacted to the loss of Brandon Hunter to the Charlotte Bobcats in Tuesday’s expansion draft. Hunter wasn’t going to get substantial playing time in Boston this season, though he might have in the future if he continued to develop, Ainge said.

“He was the odd man out,” Ainge said.