In a move meant to jimmy open Tim Duncan's championship window just a few more inches, the Spurs obtained swingman Richard Jefferson from Milwaukee as part of a three-team deal that sent longtime defensive whiz Bruce Bowen and forward Kurt Thomas to the Bucks and landed center-forward Fabricio Oberto in Detroit from Milwaukee.

In doing so, the Spurs swapped three of their oldest players for a proven NBA scorer who just celebrated his 29th birthday Sunday.

"He's an athlete," Spurs general manager R.C. Buford said, citing what foremost attracted the team to Jefferson. "There are very few players in the NBA who have played all 82 games over the past two years and scored 20 points a game. Richard is one of them."

In Jefferson, a 6-foot-7 forward entering his ninth season, the Spurs hope to have found a proven fourth scorer and an insurance policy for increasingly brittle guard Manu Ginobili.

Jefferson averaged 19.6 points per game in 2008-09, his first season with the Bucks after seven with the Nets. He started in all 82 games and made 43.9 percent of his shots - including a career-high 39.7 from 3-point range.

Tuesday's deal came to fruition only after talks with New Jersey regarding one of Jefferson's former Nets teammates - eight-time All-Star Vince Carter - came to a halt.

According to an Eastern Conference executive, Bowen, Oberto, Thomas and Roger Mason Jr. had been offered to the Nets in exchange for Carter and the Nets' first-round pick in Thursday's draft. The Spurs balked when the Nets asked for additional considerations, then turned their focus to Jefferson.

For the Bucks, the move was mostly a salary dump, meant to clear their ledger of the $29.2 million owed Jefferson over the next two seasons in preparation for the NBA's anticipated free-agent bonanza of 2010.

All three of the Spurs involved in the deal will be in the final years of their contracts next season. Bowen's $4 million deal and Oberto's $3.8 million deal are only 50 percent guaranteed for next season, making them easy targets for teams looking to shed salary.

Where the Bucks, like most other teams, were hoping to cut payroll, the Spurs apparently had no qualms with increasing theirs. Tuesday's deal helped push them $4.5 million over the luxury tax threshold and probably takes them out of marquee free-agent bidding in 2010.

For the Spurs , Jefferson - who they first pursued at the trade deadline last season - becomes their de facto 2010 signee.

"We had created some advantages through the contracts we had in place and with free agency in 2010," Buford said. "We wanted to take advantage of them when we could take advantage of them. This was the appropriate time to do that."

To get Jefferson, the Spurs were forced to part with a trio of role players who had carved a special place in the team's hierarchy. In his eight seasons in San Antonio, Bowen, 38, was part of three NBA championship teams, earned seven of his eight all-defensive team nominations and was widely regarded as a pillar of the community.

"I don't know that there's any way you can prepare for it," Bowen said. "It is a business, but it's hard to take out the personal feelings having been here so long."

Oberto, 34, helped the Spurs win titles in 2005 and 2007. The 36-year-old Thomas quickly became one of the most respected voices in the Spurs' locker room after his arrival from Seattle at the 2008 trade deadline.

As such, the Spurs didn't pull the trigger on Tuesday's deal without a tinge of remorse.

"When you lose that camaraderie, there's a big hole in your heart," Buford said.

The Spurs will next turn their attention to Thursday's draft and the NBA's looming free agency period, with an eye toward filling out their frontline. Tuesday's deal left them with just three big men under contract for next season - Duncan, Matt Bonner and Ian Mahinmi.

The Tilt-A-Whirl does not stop for Bowen and Oberto. Milwaukee plans to waive Bowen. The Pistons, who sent Amir Johnson to the Bucks as part of the deal, have the same fate in store for Oberto.

Both players will become free agents on July 1. Per league rules, they would have to wait 30 days before re-signing with the Spurs .

Herb Rudoy, Oberto's agent, said it was premature to speculate whether his client would return to San Antonio, but he wouldn't rule it out.