Kansas City, MO (Sports Network) - Wilson Betemit hit his first career grand slam to back five innings from Bruce Chen, as Kansas City rallied from an early deficit to best Oakland, 6-3, in the rubber match of a three-game set from Kauffman Stadium.
"He threw me a changeup middle-in and I swung the bat good," said Betemit of the pivotal nine-pitch at-bat. "I'm just really happy, my first grand slam."
Billy Butler hit a two-run homer and walked twice for the Royals, who won the final two contests in the series.
Chen (10-7) allowed six hits and three runs with two strikeouts to win for the first time in three starts. Joakim Soria turned in a scoreless ninth for his 38th save.
Mark Ellis collected two hits and drove in a run, while Matt Carson homered and Kurt Suzuki added an RBI single for the Athletics, who have dropped three of four.
Trevor Cahill (16-7) was charged in defeat for six hits and six runs over five full frames.
Kansas City forged ahead for good in the bottom of the third, erasing a three- run deficit.
Mitch Maier doubled with one out, then Jarrod Dyson followed with an infield single. Mike Aviles popped out but Dyson swiped second ahead of Butler's walk that loaded the bases. Betemit then put the Royals ahead, 4-3, when he cleared the wall in right for a grand slam.
"You've just got to tip your cap," Cahill said. "He made me throw a pitch that he liked. He fouled off the ones that I thought were good. It was just an overall good at-bat and he won the battle."
Aviles stroked a one-out single in the fifth, then Butler made it 6-3 for the home team with a two-run blast to center.
Gil Meche, Blake Wood and Robinson Tejeda followed with scoreless innings in relief of Chen.
Soria walked Cliff Pennington and Crisp with two down but fanned an agitated Daric Barton on a called third strike to end the game.
Oakland struck for two runs in the first as Coco Crisp singled, moved to second on a Barton flyout and scored on Ellis' base hit. Suzuki followed with a single to score Ellis.
Carson's one-out solo homer in the second made it 3-0 for the visitors.
Chen reached double digits in wins for the second time in his career, after a 13-win season with Baltimore in 2005...Soria has converted 31 consecutive save opportunities dating back to May 6 at Texas...The game was delayed for exactly one hour due to rain...Both clubs resume play on Friday with the Royals remaining home to welcome Cleveland and the A's continuing their road trip in Minnesota.