Boston — They played against each other in high school, teamed up in college and were acquired by the same team in the NBA.

The familiarity between JaJuan Johnson and E'Twaun Moore should ease their transition from Purdue to the Boston Celtics. But that partnership also can end before they play their first pro game.

"It's kind of individual," Moore said Monday. "You can't go as two at a time every time."

And Johnson is the one.

As college freshmen, the 6-foot-4 Moore was a better player than the 6-10 Johnson. The guard from East Chicago, Ind., led Purdue in scoring in each of their first three seasons. But as seniors, Johnson, an Indianapolis native, piled up the honors — first team All-American and player of the year and defensive player of the year in the Big Ten.

Both considered entering the draft after their junior seasons but decided against it.

"It was a great choice for both of us," Johnson said. "It gave us an extra year to just really develop our game, mature more. We won our senior year and that's important, too."

The Boilermakers were 26-8 last season, finishing second in the Big Ten. Johnson and Moore won 107 games in their careers and at least 25 games in each of their four seasons.

"JaJuan has definitely grown a whole lot confidence-wise and on the court and off the court being more vocal and being more of a leader," Moore said. "I was glad last year when he decided to come back to school because I almost thought I was going to lose him, but he definitely came back better than ever."

Johnson improved his dribbling, defense and mid-range jumper. While Moore may be a longshot to stick with the Celtics, he did improve as a senior. He scored a career-high 38 points against then-No. 2 Ohio State in a 76-63 win on Feb. 20.

"It definitely helped me a lot when it came to draft time," Moore said. "Teams could see I played well in big games."

They showed their new Celtics jerseys at a news conference. Johnson chose No. 12, the number his mother wore in high school. Moore, a fan of the flashy playmaking of point guard Jason Williams, went with the number Williams once wore, 55. Williams, a star at Florida, is retiring after 12 NBA seasons, winding up with Memphis this year.

"We definitely can both motivate each other and push each other through hard times," Johnson said, "so it's definitely great we both got chosen to the same team and, hopefully, we can both come and be successful."

Johnson has a much better chance.

At 220 pounds, he needs to put on weight but already is a solid all-around player. As a senior, he averaged 20.5 points, 8.6 rebounds and 2.3 blocks.

"He's gotten a lot better," Moore said. "Each year, his scoring went up. Defensively, he's definitely gotten better and I don't see why it would stop now."

The Celtics have just six players under contract — starters Paul Pierce, Kevin Garnett, Ray Allen, Rajon Rondo and Jermaine O'Neal and 2010 draft pick guard Avery Bradley. General manager Danny Ainge said he would make a qualifying offer this week to Jeff Green, meaning the Celtics would have the right to match any offer he receives.

Gilbert Brown, undrafted after a senior season as a swingman for Pittsburgh, was to work out for the Celtics on Monday, Ainge said.

With three guards signed, there could be a spot for Moore.

"It seems like time in and time out, he was the one to hit those big shots for us," Johnson said. "Him playing at a high level since our freshman year helped me to really bring my game up to where his was."

Both are 22 years old — Johnson was born 17 days before Moore in 1989 — and their maturity was one factor that impressed the Celtics.

"They've played in a lot of big games in a lot of hostile environments and they've been ranked very high at times of their college career and been the ones that have been expected to win," Ainge said. "So they've been through a lot and I think that that can only help as they're getting ready for the NBA."

They may have to prepare for a while without coach Doc Rivers and his staff. The current collective bargaining agreement is set to expire at the end of Thursday with a lockout possible after that.

"I'm not too concerned," Johnson said, "Pretty much you can only focus on the things we can control and that's really, right now, just working out and continue to get better as a player."

In high school, Johnson, Moore and Robbie Hummel, a native of Valparaiso, Ind., discussed going to Purdue together. Hummel will be entering his senior year.

Johnson and Moore were so good as seniors that they have a shot to remain teammates in the NBA.

But Ainge said it was just a coincidence that he drafted two players from the same college.

"How ironic it was," Moore said. "What's the chances of that happening?"