Denver ? The Colorado Rockies traded outfielder Preston Wilson and picked up outfielder Eric Byrnes in a pair of trades Wednesday with Washington and Oakland.

The Rockies sent Wilson and cash to the Nationals for right-hander Zach Day, outfielder J.J. Davis and a player to be named later or cash. Colorado also sent left-hander Joe Kennedy and right-handed reliever Jay Witasick to the Athletics for Byrnes and minor-league prospect Omar Quintanilla.

“We believe we’ve added some good, young talent that will help us in our rebuilding process,” Rockies general manager Dan O’Dowd said.

Wilson was one of Colorado’s more popular players after leading the majors with 141 RBIs and making the All-Star team in 2003, but is due to make $5.7 million the rest of this season and will become a free agent.

He could be just what the NL East-leading Nationals need for a lineup that has produced the fewest runs in the major leagues and is tied for the fewest homers. With cleanup hitter Nick Johnson on the disabled list, the Nationals were reduced to using utility players such as Carlos Baerga and Wil Cordero in the No. 4 spot in the order.

Wilson leads the Rockies with 15 homers and 47 RBIs, though he’s been plagued by a sore knee and hit just .258 with 77 strikeouts.

The deal, which has been in the works for a few days, was completed after Colorado agreed to pick up part of Wilson’s salary.

“We love what Preston has done for us, but he more than likely wasn’t going to be a part of our rebuilding process,” O’Dowd said.

Day opened the season in Washington’s rotation and was moved to the bullpen after a clash with manager Frank Robinson. The Nationals were close to trading Day before he went on the disabled list because of a broken wrist in May after he went 1-2 with a 6.75 earned-run average.

Davis opened the season with the Nationals because of his power potential, serving as an extra outfielder and pinch hitter, but was sent to the minors in May after going 6-for-26 (.231) with two RBIs in 14 games. The Rockies immediately optioned him to Triple-A Colorado Springs.

Byrnes earned a $2 million contract from the A’s after setting career highs in nearly every offensive category in 2004, but seemed to fall out of favor with manager Ken Macha and has been the subject of trade rumors since the offseason. He hit .266 with seven home runs and 24 RBIs for the A’s.

“Byrnes is the kind of player who can complement our roster in a lot of ways,” O’Dowd said. “He’s not the youngest player (29), but he’s someone who’s close to what we’re looking for.”

Getting Byrnes also allows the Rockies to get rid of Kennedy.

He set a team record by a left-hander with 11 wins last season and was named Colorado’s opening-day starter this year, but was headed to the bullpen following the All-Star break after going 4-8 with a 7.04 ERA.

Oakland will use Kennedy out of the bullpen at first and could move him to the rotation if things work out.

Witasick, a former Kansas City Royal who played for Oakland in 1996-97, was one of Colorado’s most consistent relievers after signing a minor-league contract with Colorado, going 0-4 with a 2.52 ERA in 32 appearances primarily as a setup man.

It was tough for the Rockies to unload Witasick, particularly with the problems they’ve had in the bullpen, but he’s 33 and will be a free agent at the end of the season.

Earlier Wednesday, the A’s acquired outfielder Jay Payton and cash from Boston for right-handed reliever Chad Bradford.