KANSAS CITY, Mo. -- Jason Vargas was on top of his game and made sure the Kansas City Royals stayed atop the American League Central standings.

Vargas threw a three-hitter and second baseman Omar Infante hit a two-run homer as the Royals shut out the Oakland Athletics 3-0 on Wednesday night.

Vargas, who gave up two hits in the first inning, retired the final 23 batters. It was his 11th career complete game and his sixth shutout. His previous shutout was Sept. 24, 2013, against the A's while with the Angels.

"It's fantastic to come back after a loss last night," Vargas said. "We played a great game from top to bottom."

The Royals just didn't lose Tuesday, but the Athletics banged out a season-best 20 hits in an 11-3 rout.

Vargas gave credit to catcher Salvador Perez for calling an excellent game.

"Salvy just put down good fingers back there and we were executing good pitches, keeping them off balance and playing good 'D,'" Vargas said.

The Royals (65-54) have won 12 of 14 and remain in first place in the AL Central, a half-game in front of the Detroit Tigers.

Vargas (8-6) struck out four and walked none. He allowed only one batter past first base. He threw 23 of his 97 pitches in the first inning and needed only five pitches in the ninth. He did not throw more than 13 pitches in an inning after the first.

Left-hander Scott Kazmir (13-5) absorbed the loss, giving up three runs and seven hits, with Infante's third-inning blow the biggest.

"One pitch, other than that he really gave up nothing," A's manager Bob Melvin said. "A ground ball we don't make a play at first and that ends up being the third run. He did his job. It was just one pitch was a two-run homer."

Infante homered in the third inning after right fielder Nori Aoki singled as the Royals grabbed a 2-0 lead.

"It felt good," Infante said. "I made good contact. I was aggressive with a fastball. I saw it well."

Infante hit a 2-0 pitch over the Royals' bullpen in left field for his first home run since June 27, a span of 149 at-bats.

"The pitch to Infante was frustrating," Kazmir said. "I was trying to go sink, low and away and it ended up staying belt high, middle in. I just didn't hit my location."

The Royals threatened in the fourth inning when designated hitter Josh Willingham singled to left, stole second and moved to third with one out on Kazmir's errant throw on a pickoff attempt. Willingham, however, was stranded as center fielder Lorenzo Cain grounded out and Kazmir struck out shortstop Alcides Escobar.

Vargas, who was making his third start since an appendectomy last month, pitched his way out of trouble in the first inning. After retiring the first two batters, third baseman Josh Donaldson doubled and moved to third on designated hitter Jonny Gomes' infield single. Vargas struck out catcher Mike Norris to end the inning.

"He's one of those guys that's hard to sell out on a certain pitch," Donaldson said. "He does a real good job of manipulating the zone. When he's on, he's tough."

The Royals manufactured a run in the fifth inning, which rookie third baseman Christian Colon started with a bunt single. Aoki's sacrifice bunt moved Colon to second and he went to third on Infante's infield single. Perez flied out to right, deep enough to bring Colon home.

Kazmir could only admire Vargas' work from the other side.

"I was actually watching on TV in between some of those innings. He was hitting every corner -- up and in and low and away. He was mixing it up nice," Kazmir said.

NOTES: A's 1B Kyle Blanks, who has missed 43 games with a left calf strain, is 3-for-5 with three walks and a home run in two rehab games for Triple-A Sacramento. ... Royals rookie INF Christian Colon started his second game at third base. 3B Mike Moustakas, who is hitting .145 against left-handers, was used as a defensive replacement late. ... Royals RHP James Shields, who has a 1.63 ERA since July 7, will start the series finale against the A's. Oakland's starter will be RHP Jeff Samardzija, who has yielded six home runs in 49 2/3 innings with the A's. ... The A's have outscored the opposition by 172 runs, more than double the next-closest team.