His Royals, on the other hand, did not hit anything out of the park and they now are last in AL homers with 92 to the A's 93. The other A's homers on Sunday were a three-run blast by Ryan Sweeney and a solo shot by Kurt Suzuki.
"It was a little windy, but they were all hit," Hillman said. "Just balls up and out over the plate."
The A's four homers matched their one-game high this year, achieved three times previously.
"Home runs seem to come in bunches," Crosby said. "I think personally they do and team-wise they do. I don't know the reason for it. But if guys' swings are going well, that's usually when it happens, and guys are swinging well right now."
This was only the second multihomer game in Crosby's seven-year career.
The A's jumped on Royals starter Luke Hochevar for four runs in the second inning, topped off by homers on back-to-back pitches.
Jack Cust led off with a walk and Suzuki doubled. A leaping catch by shortstop Yuniesky Betancourt kept Tommy Everidge's line drive from doing damage. Sweeney, however, took up the slack with a three-run homer to right field. On the next pitch, Crosby sent a homer high over the left-field wall.
"Anytime a guy hits a home run before you, your pitcher wants to get back in the rhythm," Crosby said. "And I figured he was going to try to throw a fastball by me, and I was on time for it."
Hochevar labeled the two deliveries that left the yard in front of 19,439 witnesses as "unexecuted" pitches.
"The one to Sweeney was supposed to be a cutter up and in. I threw it down in the zone and, for most lefties, that's a power zone," Hochevar said. "And then the one to Crosby, I was just trying to go with a four-seam down and away and it ran back over the middle of the plate, belt-high, and you don't usually get away with many of those."
After that uprising, Hochevar held the A's scoreless through the seventh inning. He wound up making 114 pitches while giving up seven hits with three walks and six strikeouts.
And at least the Royals made it easier for Hochevar with some fine defensive plays -- three by Betancourt at shortstop. He made a leaping catch of a wicked liner and ranged into center field for to snap a difficult popup. But the play that caught Hillman's attention came in the first inning, when Betancourt went far to his left for a stop and glove-flipped the ball to Willie Bloomquist at second base for a forceout.
"That's probably the best play he's made to his left so far," Hillman said.
Alberto Callaspo made a diving stop at third base, too.
On another positive note, the Royals matched the A's nine hits and continued their recent hitting splurge. In their past seven games, the Royals have batted .325 (82-for-252) while averaging 6.1 runs per game.
Billy Butler had two more hits and is 14-for-23 (.609) in a six-game streak.
But not enough of the offense came early against A's rookie left-hander Brett Anderson, who held the Royals scoreless for the first six innings, allowing just three singles.
"He's got a good breaking ball, and really his fastball was the best pitch for us to go after and hit," the Royals' unrelated Josh Anderson said. "The slider's obviously good. He throws that slider after a lot of fastballs. It's hard and it throws guys off. If he throws it for a strike, it's a tough pitch to hit."
But Brett Anderson's giddy spell was abruptly ended.
When the seventh began with Mark Teahen's single, Callaspo's double and Brayan Pena's RBI single, Anderson was out of the game. Right-hander Michael Wuertz took over and two more runs scored, both on force plays that sandwiched Betancourt's infield single.
That cut the A's lead to 4-3, but, batting against reliever Roman Colon, Suzuki made it 5-3 with a towering home run to left field that bounced up against a window at the Royals Hall of Fame. And, in the ninth, Crosby led off with a homer to right field against lefty John Bale.
The four homers given up tied the Royals' season high; they also surrendered four on July 11 at Boston.
So the A's took the series between the two last-place teams and the Royals wound up with a 2-4 homestand.