ST. PETERSBURG, Fla. -- Dominant pitching, solid fielding and just enough hitting have taken the Tampa Bay Rays to first place in the American League East.

Tampa Bay (23-19) sits alone atop the division after a 3-0 win on Thursday night at Tropicana Field.

Alex Colome and four relievers combined for the Rays' fourth shutout of the season.

The Athletics (14-29) has lost three straight and seven of their last eight for the worst record in the majors.

"You want to be in this position at the end of the year," Rays manager Kevin Cash said. "It's always nice to be here where we're at, so we change anything, but I don't think we'll get too caught up in where we're at at this given point. We just want to play good baseball."

Tampa Bay got an RBI double and solo home run from designated hitter David DeJesus, and that was all the scoring the pitching staff needed. Colome (3-1) pitched five innings and the bullpen continued its strong efforts, allowing only two hits in the final four innings.

"The only thing I did was be more aggressive, attacking the zone," said Colome, who had struggled in his last two starts. "Tonight, first pitches were strikes, made good pitches. I know I threw the ball well."

The A's opened the game with a leadoff triple by center fielder Billy Burns, but he left early when shortstop Marcus Semien followed with a fly ball to deep center and wasn't able to score.

The Rays got out of the inning, stranding Burns at third. The A's didn't get many opportunities to score after that.

"Not a good game for us, obviously," A's manager Bob Melvin said. "Got sloppy at the end, had a chance to get a lead. Jesse (Chavez) pitched well, but (we) never really put any pressure on them."

DeJesus drove in the game's first run in the fourth, then added an insurance run in the seventh with his fourth home run of the season.

Rays left fielder Brandon Guyer manufactured another run, reaching on a single, stealing second and third, then scoring on a comebacker that catcher Bobby Wilson hit for a 3-0 lead.

Reliever Edward Mujica fielded the ball and threw to first for the out but left the game with a trainer holding his right hand as he walked off the field. Melvin said he fractured his right thumb and suffered a laceration that required stitches, so he's headed to the disabled list.

"We didn't have that great of at-bats," Melvin said. "We were chasing high fastballs, (Colome's) breaking pitch was pretty good. We made him throw some pitches, but when we did have baserunners, we couldn't get them in."

Chavez held Tampa Bay to three hits entering the seventh but gave up DeJesus' home run and put Guyer on, with all three runs counting against him.

Tampa Bay showed off its new 1-2-3 bullpen combo for the final three innings, with right-hander Kevin Jepsen, left-hander Jake McGee and right-hander Brad Boxberger each pitching a scoreless inning.

Boxberger improved to 12 for 12 in save opportunities. Right-hander Steve Geltz got the relief started with a perfect sixth.

Oakland had two singles in the ninth to put the tying run at the plate, but Boxberger got third baseman Brett Lawrie to strike out for the final out.

Colome's only real trouble came in the fourth when Oakland loaded the bases on a single by catcher Stephen Vogt, a walk by first baseman Max Muncy and an infield single by Lawrie. Former Rays outfielder Sam Fuld grounded out to first to end the threat.

Chavez kept the Rays' bats in check, holding the Rays to three hits in the first five innings.

Tampa Bay got on the scoreboard in the bottom of the fourth. Third baseman Evan Longoria reached on a walk and scored on an RBI double by DeJesus for a 1-0 lead.

Colome bounced back nicely after coming in with a 10.61 ERA in his last two starts. He threw 86 pitches, including 57 for strikes, and left with a chance at the win with a 1-0 lead.

NOTES: Rays LHP Drew Smyly will not have season-ending surgery for a small labrum tear as previously reported and will choose an eight-week rehab in hopes of returning in late July. ... Another rehabbing Rays pitcher, LHP Matt Moore, will throw two innings in an extended spring training game on Saturday. He's recovering from Tommy John surgery. ... The San Francisco Chronicle reported that the A's will call up RHP Kendall Graveman to start Saturday's game against the Rays, filling in for LHP Drew Pomeranz (sprained left AC joint), who is on the disabled list. Graveman made four starts in April and went 1-2 with an 8.27 ERA, but he is 2-1 with a 1.85 ERA at Triple-A since then.