Updated

Even after their first home loss since April 20, the Tampa Bay Rays were upbeat.

The team still owns the best record in the majors at 19-9, so the players figured they'd celebrate Cinco De Mayo despite losing 4-3 in 12 innings to the Oakland Athletics on Saturday night.

They did so with a three-piece mariachi band playing in the clubhouse. Carlos Pena wouldn't say whether he was the one who hired the musicians.

"That's classified," Pena said.

Jonny Gomes got a huge hit against his former team, a go-ahead homer in the 12th for Oakland, and made a big play on defense. He replaced Seth Smith in left field in the seventh and made a diving catch to rob Pena of an extra-base hit in the 10th.

"I know he plays hard. He goes after every ball hard, so that doesn't surprise me at all," Pena said. "I was amazed at the catch and I think all of us were shocked when he came up with that ball."

Gomes, who spent six seasons with Tampa Bay from 2003-08, hit his fifth home run of the season off reliever Joel Peralta (0-1) to stop the Rays' six-game winning streak.

"At this point, I've got a lot of ex-teams," Gomes said, "and I've got nothing but respect for that team over there. This isn't, rub it in Tampa's face, or it's awesome because it's against my old team. It's just good to get a win against the best team in baseball right now."

Pena, Ben Zobrist and Elliot Johnson all homered as Tampa Bay rallied to bail out Jeremy Hellickson after an ineffective start. But the Rays fell to 13-2 at home and failed in their bid to become the first major league team to reach 20 wins this season.

"The former Rays thing doesn't really come into play, but Gomes has come up big for us this year," A's manager Bob Melvin said. "But if you're giving out a player of the game, then it's him because he didn't even start the game, but he made the two biggest plays with the catch and then the homer."

The A's worked long at-bats to run up Hellickson's pitch count and chase last year's AL Rookie of the Year after 3 2-3 innings.

"I felt good, though. I just have to throw more strikes," Hellickson said. "I'm not pleased at all, though."

Hellickson threw 52 pitches through two innings and finished with 102 in the shortest outing of his young career. He gave up three runs, two earned, on five hits and three walks.

"Sometimes you can be effective not scoring runs on a guy," Melvin said. "We didn't cash in as often as we would have liked to with a guy that threw that many pitches in a short time, but it got him out of the game."

Josh Reddick also homered for the A's. Brian Fuentes (2-0) worked two scoreless innings and Grant Balfour, another former Ray, got three outs for his seventh save in nine chances.

Tampa Bay had a chance to win in the 11th when Sean Rodriguez reached third with one out after a leadoff double that dropped between three players in shallow right field. Johnson, however, struck out when he fouled off a suicide squeeze attempt with two strikes and Desmond Jennings flied out.

Johnson homered in the third, Zobrist in the fourth and Pena in the fifth to tie the game. All three came from left-handed hitters — manager Joe Maddon intentionally put six left-handed bats in Tampa Bay's lineup.

Oakland starter Bartolo Colon had held left-handed batters to a .198 average coming in, but he ended up throwing 83 pitches over five innings and giving up eight hits.

"We had a lot of good at-bats," Maddon said. "We hit some balls hard without any luck."

Reddick hit his fifth homer in the first and Cliff Pennington scored in the third after reaching on an error by second baseman Ben Zobrist. Kila Ka'aihue drove in Pennington with a single, and Reddick added an RBI single in the fourth.

Rays relievers J.P. Howell, Jake McGee, Burke Badenhop and Fernando Rodney picked up the slack for Hellickson. Brandon Gomes worked himself out of a bases-loaded jam in the 10th.

"It felt like no team wanted to execute enough to win the game," Melvin said. "Each team had their chances, but didn't take them. This game just had a crazy feel to it."

NOTES: After the game, the Rays optioned Brandon Gomes to Triple-A Durham and said they will make a corresponding roster move before Sunday's game. ... It was Maddon's 1,000th game as Tampa Bay manager. He is 514-486 in seven seasons. The club had just 518 wins prior to his arrival. ... Maddon became the fourth manager with at least 1,000 games with his current team. He joined Mike Scioscia (1,972) of the Angels, Minnesota's Ron Gardenhire (1,647) and Philadelphia's Charlie Manuel (1,162). Detroit's Jim Leyland will join the group Sunday. ... Will Rhymes made his third start at third base, the most of any Rays player since Evan Longoria was placed on the disabled list Tuesday. ... Pena snapped a 0-for-12 slump with an infield single in the first. ... The loss snapped a streak of six consecutive wins on Cinco De Mayo for the Rays. ... The announced attendance was 23,890.