OAKLAND, Calif. (AP) – Shane Costa doubled twice and drove in a run and Seth Etherton won in the majors for first time in more than a year in the Kansas City Royals’ 6-4 victory over the Oakland Athletics on Monday night.

Emil Brown had three hits and drove in a run and Matt Stairs and Doug Mientkiewicz had RBI doubles for Kansas City. The Royals won for only the second time in 17 games, improved to 4-22 on the road and gave manager Buddy Bell his 400th win.

Frank Thomas hit his 458th career homer and 10th of the season, a solo shot to left in the fifth off Etherton (1-0), who made his first start of the season after the Royals acquired him Saturday from the San Diego Padres.

Oakland had been looking to get back on track following a 1-6 road trip in which the A’s dropped four games by one run. Instead, they lost for the ninth time in 10 games to fall a season-worst five games under .500 (23-28).

Nick Swisher walked with the bases loaded in the second for Oakland and hit a solo homer in the ninth, his 15th. Eric Chavez had an RBI groundout in the seventh.

Dan Haren (4-5), who had his three-start winning streak snapped in a 3-2 loss at Chicago last Wednesday, threw a career-high 122 pitches in his second straight defeat.

He struck out the side in the sixth, retiring No. 9 hitter Andres Blanco on a called third strike to end a 14-pitch at-bat. Haren also got Royals designated hitter Stairs to strike out swinging in his first three at-bats before Stairs doubled in a run in the seventh against Haren’s replacement, Randy Keisler.

Haren matched his career high with nine strikeouts and allowed eight hits and five runs in 6 2-3 innings.

Costa hit an RBI double in the second after Brown scored on an error moments earlier to put the Royals ahead. Costa doubled again in the fourth for his first career two-double game.

John Buck added a run-scoring single for the Royals, who began the middle series of an 11-day, 10-game trip through three cities.

Etherton threw 88 pitches through four innings after a 12-pitch fourth and was done after five innings and 100 pitches. He allowed two runs and six hits, struck out two and walked two.

Etherton, a former Oakland pitcher, won for the first time since May 18, 2005, a 13-6 A’s win over Boston. That was his first big league victory since Sept. 1, 2003, for Cincinnati at Milwaukee.

Ambiorix Burgos got three outs for his sixth save.

Bell has 55 wins with the Royals after previous managerial stints with Detroit and Colorado. His overall record is 400-568.

Notes: Kansas City’s Mark Grudzielanek stole his first base of 2006 in the seventh. … Thomas is a .310 career hitter (188-for-607) with 35 homers and 117 RBIs in 169 games against the Royals. … Royals third-base coach Luis Silverio was not with the team after returning home to deal with a family illness. … The A’s plan to decide Tuesday what to do with injured starter Rich Harden, who has been out since April 27 with a strained lower back. The right-hander threw on the side before Monday’s game and Oakland must decide where to send him next.

AP-ES-05-30-06 0006EDT