KANSAS CITY -- There hasn't been much for the A's to hang their collective hat on since the All-Star break, but they were working on a nice little winning streak entering Tuesday's opener of a three-game series at Kauffman Stadium.

Not one of those come-out-on-top-in-multiple-consecutive-games kinds of winning streaks, of course. The A's have won back-to-back games exactly once since July 11.

But a winning streak it was. Emphasis on the word was.

Oakland had won the first game of its past seven series until Tuesday, when Billy Butler's mammoth three-run homer in the first inning off A's lefty Gio Gonzalez was all the offense the Royals needed on the way to a 5-2 victory.

The pitch was a fastball. High. Very high. And, eventually, far. Very far.

"It was about at his chin level," Gonzalez said after the A's fell to 27-19 in series openers on the year. "He's a powerful kid, man."

Gonzalez also gave up a homer to Ryan Shealy, a right-handed hitter who ripped a letter-high fastball the other way.

"You can't make mistakes like that," Gonzalez said.

Trying to bounce back from a wild outing against the Angels on Wednesday, when he walked five over three long innings, Gonzalez walked the second batter he faced against the Royals, and again it was a long-but-short night for the rookie.

After the walk to Mike Aviles, rookie left fielder Aaron Cunningham dropped a fly ball at the wall for an error that put runners at second and third, and Butler followed with his 10th homer of the year, a blast to left that landed in the pond from which Kauffman's iconic outfield waterfalls flow.

On the topic of omnipresence at Kauffman, it must be noted that whomever runs the massive, new, frighteningly high-definition video/scoreboard nailed it on the head when accompanying the sound system's blaring of Garth Brooks' "Friends in Low Places" with crowd shots of happily oblivious revelers during the sixth inning.

The announced crowd of 11,143 looked much smaller, with some of the paying customers no doubt steering clear of the rain that delayed the game's start by about 30 minutes, but it sure had a good time.

Friends in low places? Yes. The Royals and A's entered the game a combined 40 games out of first place in their respective divisions. So you search for the positives, and there were two that jumped out from the green-and-gold perspective.

One was the evening of rookie first baseman Daric Barton, who seems to enjoy hitting in September.

It was during this month last year that hit himself into the playoff dreams of A's fans by raking his way to a .347 batting average in 18 games with Oakland to end the year. Barton, however, mostly struggled in the season's first four-plus months before starting to climb back toward respectability in late August.

He entered the series 12-for-33 over his past 10 games, ripped an RBI triple in the second, hit his eighth homer of the year in the fifth, walked in the seventh and singled in the ninth.

"He looks a lot more confident standing there," A's manager Bob Geren said. "Even on his takes."

Asked about his September surges, Barton said, "I don't know what it is, man. I just wish that April, May, June, July and August were the same."

The other big positive for the A's was the big league debut of Josh Outman, a hard-throwing lefty who hit 96 on the stadium radar gun on his way to two scoreless innings of two-hit work.

"I liked what I saw there a lot," Geren said.

In the end, though, it was the end of one streak and the continuation of another. Gonzalez, who threw 96 pitches in four innings, hasn't won since Aug. 12.

"It was a little tough for me, [giving up a] three-spot in the first," Gonzalez said. "But you've got to just let it go."