ANAHEIM, Calif. -- Although the season has not yet reached the halfway point, neither the Oakland A's nor Los Angeles Angels seem to have much of a chance to contend for a playoff spot. So it's the little victories that mean a lot.

The A's had won back-to-back games only once this month before coming to town to face the Angels, but they pulled it off with a win Thursday and another Friday night, thanks to Khris Davis' tie-breaking three-run homer in the eighth inning that led to a 7-4 victory at Angel Stadium.

"It's a confidence booster for sure," Davis said.

The win moved the A's ahead of the Angels in the American League West, dropping the Angels into last place, 16 games behind first-place Texas. The Angels have lost five in a row, and at 31-43, are 12 games under .500 for the first time since Aug. 29, 2013.

The A's offense, which has struggled most of the season, pounded out 14 hits, including three each from Stephen Vogt (homer, two singles) and Marcus Semien (double, two singles).

The big hit, though, came off the bat of Davis.

The game was tied at 4-4 through five innings, and with both starters out of the game, it became a battle of bullpens. Angels reliever Fernando Salas looked sharp in the seventh inning, retiring the side in order on just six pitches.

But in the eighth, he quickly found trouble, allowing a single to Vogt and a double to Danny Valencia to begin the inning. Salas (3-4) got ahead in the count to Davis 0-2, but then grooved a 92-mph fastball up and out over the plate to Davis, who hit a line drive over the fence in left-center for his 18th homer of the year.

"Not really," Davis said when asked if he was surprised to get an 0-2 fastball. "I kind of felt like they were elevating on me so I was looking for it. In that situation I just had enough savvy to know they were trying to climb the ladder, and they didn't climb it high enough."

Salas likely would not have pitched the eighth if he hadn't gotten out of the seventh so swiftly.

"He just got beat with a couple off-speed pitches up," Angels manager Mike Scioscia said. "Vogt lines one to left and then he left one up to Valencia and he hits it down the line. He had a chance to make a pitch on Davis and give him credit, he left a fastball over the plate and Davis didn't miss it. It's just that some mistakes caught up to him."

Neither starting pitcher stuck around very long. A's starter Eric Surkamp remained winless on the season after giving up four runs (two earned) on five hits and two walks in 3 2/3 innings.

Angels starter Jered Weaver, who threw a three-hit shutout against the A's in his last start five days ago, lasted just 4 2/3 innings this time around, giving up four runs on eight hits and one walk.

"I think Jered just lost a lot of counts," Scioscia said. "He had some trouble when he got into some good counts. It just seemed he wasn't able to make that pitch like he did last weekend up in Oakland. Those guys put together some good at-bats and had some good innings."

Four Oakland relievers -- Fernando Rodriguez, Ryan Dull (2-2), John Axford and Ryan Madson (14th save) -- combined to shut out the Angels over the final 5 1/3 innings to finish it.

Johnny Giavotella had three hits and Mike Trout two for the Angels, who are not throwing in the towel on the season according to Scioscia.

"When we start doing things on a consistent basis and start controlling the process better, winning each little situation in a game and getting the game on our terms, you'll see the wins come," Scioscia said. "We're confident in that. But it comes back to controlling the process. And there's so many facets to this game you have to perform well that lead up to a win, and we've been a little short in some areas."

NOTES: Angels 3B Yunel Escobar was not in the starting lineup, dealing with a sore left knee that forced him out of the game Thursday after running out a ground ball. INF/OF Jefry Marte got the start at 3B, and 2B Johnny Giavotella took Escobar's leadoff spot in the lineup. ... Athletics LHP Rich Hill, out since May 30 with a strained left groin, threw a 35-pitch bullpen session and reported feeling good. He'll begin a rehab assignment for Class-A Stockton on Monday and if all goes well, could rejoin the rotation by the end of next week. Hill is 8-3 with a 2.25 ERA in 11 starts this season. ... Angels RHP Nick Tropeano (sore shoulder) completed his minor league rehab assignment but was optioned to Triple-A Salt Lake instead of joining the major league roster. At 3-2, Tropeano is the only Angels starter with a winning record and his 3.25 ERA is better than any of the five currently in the rotation. ... With his 13th home run Thursday, A's SS Marcus Semien leads all American League shortstops.