Doc Rivers and Danny Ainge were in Los Angeles during the NBA Finals when Ainge started talking about the draft.
Ainge had been scouting college talent for a while, and he had a short list of players he thought would work in Rivers's system.
"I was trying to slow Kobe [Bryant] down more than worry about a college guy," Rivers said.
Later, Rivers had barely kissed the Celtics' championship trophy and hopped off the duck boat after the victory parade before Ainge gave him four tapes of this guard from the University of New Mexico named J.R. Giddens.
Rivers liked what he saw. Athletic. Skilled. Incredible wingspan.
But what stuck out most to Rivers was the way Giddens shut down opponents.
"He has a chance to fight for minutes right away because of his defense," Rivers said.
So with Giddens still on the board at No. 30 last night, the Celtics submitted his name as their first-round pick.
"I think he's a playmaker at the defensive end," Ainge said. "This guy gets steals, blocks shots from the guard position. He's a playmaker at the defensive end and he's a pretty darn good offensive player."
Giddens, who had some character issues early in his college career (he transferred from Kansas), was grateful for the chance to join a champion.
"I just want to thank [the Celtics] for having confidence in me," he said. "I'm truly blessed. I'm so thankful to be in that organization, to be in that city, the history with the Celtics. It's truly amazing to be in that organization."
Rivers said the Celtics were going back and forth between Giddens and another player he chose not to name, but Ainge's word, plus Giddens's performance over a recent three-day visit to Boston, had the coach sold. There are some deficiencies in his game, including free throw shooting and ballhandling, but with the possibility of losing a stopper like James Posey in free agency, Gidden looked like a viable option.
"He was very competitive in that workout," Rivers said of Giddens. "His team lost a couple of games and you could see he didn't like it and he did something about it on the floor. What turns him on is winning. He hates losing. He hasn't handled losing very well and hasn't handled it probably in the right way at times. I kind of look at it as an asset more than a problem."
Giddens is personally familiar with a couple of the players on the Celtics' roster, having played in the 2003
"I got a great feel for everyone in the organization," Giddens said. "I looked at [Kevin Garnett's] and Paul Pierce's lockers. There are so many good people in that organization. I'm so excited."
Giddens went to Kansas out of John Marshall High School in Oklahoma City, but his relationship with the Jayhawks went sour not long after he was involved in a fight outside of a bar in May 2005 during which he was stabbed in the right calf.
Giddens transferred to New Mexico, sitting out the 2005-06 season, and left his problems behind, according to Lobos assistant coach Craig Neal.
"He's been through so much," Neal said. "I think he's made his mistakes. But we are proud of him. We pushed and pushed. He could have walked away."
Ainge said that once Giddens came to New Mexico where he had more guidance, he excelled.
"I thought this year when he had structure and organization in his life, I thought he played terrific," Ainge said.
Giddens said, "I've overcome those things and they made me the man that I am today. I didn't go through all those things for no reason. I think they helped me build the character I have now."
Ainge and Rivers said one of the team's top priorities is bringing back Posey. Ainge said that as good a defensive player as Giddens can be, "This has nothing to do with James Posey."
The Celtics later dealt for the 47th overall pick, Kansas State forward Bill Walker, sending cash considerations to the Wizards. The Celtics used the final pick of the night on Semih Erden, a 7-1 center from Turkey.
Walker, a 6-6, 235-pounder, averaged 16.1 points and 6.3 rebounds as a redshirt freshman for Kansas State while playing alongside Michael Beasley, the second pick in the draft.
The 20-year-old Walker played six games for the Wildcats as a true freshman before suffering a torn anterior cruciate ligament in his left knee. Walker also injured his right knee during a workout this month for Golden State and said he will have minor surgery in July that should keep him sidelined three weeks.
"It's not serious," Walker said in a telephone interview. "I will have a simple operation and be back in three weeks. I will be in Boston rehabbing."
As a second-round pick, Walker doesn't merit a guaranteed contract, and will make a minimum of $442,114 if he makes the team. He watched the draft in Topeka, Kan., with his AAU coach, mother, and other family members.
"I can't put this into words," said Walker, who visited the Celtics' training facility Monday. "This is a dream come true. I'm looking forward to getting an opportunity."
Marc J. Spears of the Globe staff contributed; Julian Benbow can be reached at email@example.com.