"I've been doing (it) the same way the whole year, whether it's good or bad," the A's shortstop said. "Just keep the same routine. Tonight I just saw the ball well."
Emil Brown and Ryan Sweeney added three hits apiece for the A's, who broke out of a weeklong offensive slump with their highest run total of the season, including a four-run sixth inning against Royals starter Brian Bannister.
The A's scored seven runs in their previous seven games before tagging Bannister and four relievers for 15 hits, matching their season-high set in a 9-7 win over Cleveland on April 11.
Crosby led the onslaught with a bases-loaded double in the sixth and a three-run homer in the eighth. Oakland's shortstop, who was just 3-for-24 in his previous six games, finished 3-for-4 with two doubles while setting a career high for RBI.
"Obviously it's nice to break out with some runs," manager Bob Geren said. "The guys have been working hard at it and they finally found some holes. When you're struggling you always have to keep saying that things will turn around, and tonight they did."
Gaudin opened the season on the disabled list after undergoing hip and foot surgery during the offseason. He was tagged for nine runs in 10 innings during his first two starts but had little problem against the Royals and their inept offense.
Oakland's right-hander scattered four hits over seven innings while striking out a career-high eight with one walk. After giving up an RBI single to Billy Butler in the third, Gaudin retired the final 12 batters he faced before giving way to Santiago Casilla to begin the eighth.
"This was really the first time where I felt in control in a sense of everything, the game, myself, my body," Gaudin said. "It's a great feeling. It took a while to get back to it but I got there."
Bannister (3-1), who was attempting to join Boston's Daisuke Matsuzaka as the majors' only four-game winners, gave up nine hits and walked one in five innings before getting pulled after allowing four straight hits to open the sixth.
"I could tell in the first inning that it wasn't going to be one of my electric nights where I felt really sharp, so I battled through it," Bannister said. "They had a great approach tonight. They took the ball the other way the whole night and didn't try to swing out of their shoes and that's kind of how you beat me."
Jack Cust, Brown and Sweeney hit consecutive singles to start the sixth before Crosby hit a 1-0 slider over the head of left fielder Mark Teahen. Teahen, who earlier misplayed another Crosby fly ball into a double, tried to make a leaping catch but the ball sailed over his glove and bounced on the warning track as Cust and Brown scored.
"I was looking for fastballs away because (Bannister) has that cutter," Crosby said.
The A's added a season-high eight runs in the eighth with some help from Kansas City's defense. Brown hit a bases-loaded fly to left that dropped between two fielders, allowing two runs to score, and second baseman Mark Grudzielanek was slow to throw to first on Sweeney's infield grounder.
Crosby then homered to right, his second of the year. It was the first home run in six games for the A's, who entered Friday tied with San Diego for the fewest homers in the majors.
The A's won despite committing an error in their 11th consecutive game, the team's longest such streak since 1985. The throwing error by Hannahan, Oakland's third baseman, accounted for Kansas City's first run.
Several Royals players and staff arrived at the ballpark only two hours before the game. A bus that was supposed to transport them never arrived at the team's hotel in San Francisco, forcing the Royals to hire cabs for the trip across the Bay Bridge during rush hour traffic.
- Oakland C Kurt Suzuki batted leadoff for the first time in his career and went 2-for-4 and scored twice. Buck, the team's leadoff hitter in 14 of the first 17 games, was dropped to the eighth spot and went 0-for-4.
- Royals CF David DeJesus was held out of the game after jamming his toe against the outfield wall while shagging batting practice before Thursday's game in Anaheim. DeJesus is expected back in the lineup Saturday.