OAKLAND, Calif. -- Another day, another walk-off win for the Oakland A's against the Tampa Bay Rays, this one even more spectacular than the first.

One day after Coco Crisp hit a walk-off single in the 13th inning to beat the Rays 1-0, rookie third baseman Ryon Healy crushed a walk-off solo home run with two outs in the ninth, lifting the A's to a 4-3 victory on Saturday night at Oakland Coliseum.

Healy's first career walk-off came moments after Jake Smolinski launched a two-run homer to left to tie the score.

"He has not been afraid of any situation that he's been in," A's manager Bob Melvin said of Healy, who played his eighth career major-league game. "His first big-league hit's a three-run home run that ends up being the big hit in the game. He went up there with fire his eyes with a tie game."

A's right-hander Kendall Graveman (7-6) appeared headed for a complete-game loss, but thanks to Smolinski and Healy, he extended his career-best winning streak to six games. He gave up three runs and nine hits, struck out four, walked one and pitched a career-high nine innings.

"You just kind of had a feeling in the dugout we were going to put something together eventually," Graveman said. "To have two walkoffs on back-to-back nights, that's fun. There's something fun happening in this clubhouse."

The walk-off win was Oakland's sixth of the season and third in five games.

"I don't think there's anything more fun than walk-off wins in baseball," Healy said. "The fact we've been able to have so many in my short eight-day career just makes winning that much better."

The A's trailed 3-1 entering the bottom of the ninth and faced closer Alex Colome, who had 21 straight saves, a Rays franchise record to start the season and one shy of tying the overall team record. Khris Davis worked a leadoff walk and, with one out, Smolinski crushed Colome's first pitch fastball for a two-run shot to left.

Smolinski said he was looking for heat on the first pitch.

"I saw him the other day and he grooved one and I took it," Smolinski said. "And after that, I saw his cutter/slider that was pretty nasty, so I told (hitting coach Darren) Bush I was going to be ready for that first-pitch heater if I got it again and I did.

"Kendall pitched amazing. We wanted to get it done for him just because he deserved that."

Colome retired Marcus Semien on a fly ball, but Healy launched his 3-2 fastball over the left-center field wall for his first career walk-off hit and second career home run.

Colome (1-3) had his first blown save of the season.

"Completely uncharacteristic of him because he's been outstanding for us all year," Rays manager Kevin Cash said of Colome. "Can't wait to get him back out there tomorrow."

Rays left-hander Drew Smyly allowed one run and six hits in six innings, struck out one and walked one but got a no-decision as his career-high seven-game losing streak stayed intact. Smyly hasn't won since May 16 at Toronto.

"When you leave the game with the lead, you know your team's got a chance to win," Smyly said. "It didn't work out tonight. It's unfortunate, but this game doesn't come easy for anybody."

Rays right-hander Matt Andriese, who pitched a two-hit shutout against Oakland on May 14, threw two perfect innings in relief, striking out two.

Rays right fielder Oswaldo Arcia went 2-for-3 with a double and an RBI but left the game with a mild right elbow strain after striking out in the top of the seventh. Cash said he expects him to be in the lineup Sunday.

Jed Lowrie had two hits in four at-bats and scored a run for the A's. Davis had an RBI single in the first inning and scored a run.

A's rookie catcher Bruce Maxwell was called up Saturday from Triple-A Nashville and made his major-league debut, grounding out in the seventh inning as a pinch hitter. Maxwell stayed in the game.

The A's took a 1-0 lead in the first inning. Lowrie grounded a one-out single to right, Danny Valencia walked and Davis lined an RBI single to center.

The Rays pulled even in the second. Corey Dickerson hit a leadoff double off the left-center field fence, moved to third on Steve Pearce's groundout and scored when Arcia lined an opposite-field single to left.

Tampa Bay added a run in the fourth to take a 2-1 lead. Pearce lined a single to right with one out, moved to third on Arcia's double off the center field fence and scored on Brandon Guyer's groundout.

NOTES: Athletics RF Josh Reddick, who has been the subject of trade rumors, was a late scratch from the lineup with a sore back that developed during Friday night's game. OF Jake Smolinski moved from center to right, and Coco Crisp moved into the lineup in center field. ... The A's placed C Stephen Vogt on the family medical leave list and called up C Bruce Maxwell from Triple-A Nashville. A's manager Bob Melvin said Vogt is dealing with a "family emergency situation" but should miss only three games. Maxwell will make his first major-league start Sunday.... A's RHP Fernando Rodriguez (strained right shoulder) was transferred from the 15-day to the 60-day disabled list, opening a spot on the 40-man roster for Maxwell. ... Rays 1B Logan Morrison (sore right forearm) was out of the starting lineup for the fifth straight game but was available to play. ... Rays RHP Brad Boxberger (left oblique strain) made his third rehab outing for Class A Charlotte and gave up one run on two hits while striking out one in an inning of work. He threw 22 pitches. "(Velocity) was very good again so that's exciting to see," Rays manager Kevin Cash said.