Kansas City, MO (My Sportsbook) - Billy Butler hit a three-run homer and finished with four RBI to lead the Kansas City Royals to a 5-2 win over the Oakland Athletics in the opener of a three-game series at Kauffman Stadium.

Zack Greinke pitched seven strong innings and earned the win for the Royals, who have won two of their last three on the heels of a four-game skid. Greinke (10-9) allowed two runs on six hits with eight strikeouts and one walk. Ryan Shealy added a solo home run in the victory.

Daric Barton homered for the Athletics, who have dropped three of their last four games.

Gio Gonzalez (1-3) suffered the loss after he allowed four runs -- three earned -- on two hits with five strikeouts over four innings of work.

The Royals jumped out to a quick 3-0 lead in the bottom of the first inning. Mike Aviles worked a one-out walk and Jose Guillen reached first base on a fielding error by Aaron Cunningham before Butler belted a three-run homer over the wall in left field.

"I got into the mentality of 'let it rip' and I didn't care if I got jammed," said Butler. "I kept my hands inside and it gave me the ability to let the balls get deeper and recognize pitches more."

In the top of the second, the visitors cut their deficit to 3-1. Jack Cust led off with a double and scored on a one-out triple by Barton.

Shealy led off the bottom of the fourth with a home run, and Barton answered with a leadoff blast of his own in the top of the fifth.

Holding a 4-2 lead, Kansas City moved ahead by three in the bottom portion of the fifth via Butler's RBI single that scored Aviles. It was the second time in three games Butler had four RBI.

Greinke tossed a perfect sixth and successfully worked around a leadoff walk to Barton in the seventh.

"He was locating his fastball very well tonight," said Barton of Greinkie. "He left a couple out over the plate, but we just didn't capitalize on those. He's just a tough pitcher."

Ramon Ramirez cruised through a 1-2-3 eighth and Joakim Soria notched his 34th save of the campaign with a 14-pitch ninth.

Game Notes

Greinke halted a four-start winless streak and in the process improved to 3-0 in his career against the A's...Gonzalez holds a 7.18 earned run average in 2008...Oakland has now failed to score more than six runs in 38 consecutive games, which is the longest streak by an AL team since 1988. That year, the Milwaukee Brewers went 40 consecutive games without a seven-run offensive output...The A's left five men on base.