OAKLAND, Calif -- Ryon Healy keyed a four-run third inning with a two-run home run and Andrew Triggs combined with three relievers on a five-hitter, leading the Oakland Athletics to a 5-1 victory over the Los Angeles Angels on Thursday afternoon.

Healy hit his second home run of the season when he sent a 1-0 pitch from Tyler Skaggs (0-1) over the left-center field wall with two outs in the third.

"He's quite the force, from the moment he got here last year," said A's manager Bob Melvin about Healy. "He plays with an edge, very confident at the plate and has power to all fields."

Before Healy's home run, Khris Davis lifted a sacrifice fly and Marcus Semien added a run-scoring single aided by center fielder Mike Trout's fielding error.

Triggs (1-0) allowed an unearned run and four hits in 5 2/3 innings. Trout, who was 0-for-2 with a walk against Triggs, said that Triggs "just kept us off-balance, working in and out. He was working both sides of the plate. His sinker was working. It's just one of those days."

Triggs pointed to the third inning as critical to the win. Besides the A's four runs, Triggs worked out of a two-on, one-out situation in the top half, allowing only one run on a groundout by Albert Pujols.

"For me personally, it was about getting my fastball command a little bit more honed-in as things got going there," Triggs said. "That inning by us was absolutely huge."

Relievers Liam Hendriks, Santiago Casilla and Sean Doolittle combined on 3 1/3 shutout innings and allowed only one hit the rest of the way. Doolittle had three strikeouts in his one inning of work in the ninth, allowing only a two-out single by Andrelton Simmons, who was 2-for-4. He was the only player in the game with two hits.

The Angels' run was unearned thanks to an error by Oakland center fielder Rajai Davis on a single by Yunel Escobar. Escobar moved to third on a groundout and scored on Pujols' groundout. Pujols was 0-for-4 and is now hitting .063 this season.

Skaggs allowed five earned runs and five hits in 5 1/3 innings.

"I think there were some highlights in there and some things that got away from him. All in all, stuff looked good," said Angels manager Mike Scioscia about Skaggs. "He lost some counts. Obviously, the walks didn't help."

The Angels' relievers were as impressive as the A's on Thursday. Blake Parker and Yusmeiro Petit pitched no-hit ball for 2 2/3 innings, collecting six strikeouts.

Healy fouled a ball off his foot in the sixth inning and was lifted from the game after he struck out.

NOTES: Angels RHP Garrett Richards will be evaluated Friday and is expected to undergo tests on his right biceps. Richards suffered right biceps cramping Wednesday which led to his exit after 4 2/3 innings. "Hopefully this is just a bump in the road," Angels manager Mike Scioscia said. Richards missed most of last season because of a partially torn ulnar collateral ligament in his right elbow. ... A's RHP John Axford, who was placed on the 10-day disabled list Wednesday with a muscle strain in his right shoulder, has been told not to pick up a ball for a week. Oakland manager Bob Melvin said Axford will likely be out for more than 10 days. RHP Sonny Gray (strained lat) will throw a bullpen session Friday. "And we will see where we are after that," Melvin said. Angels LF Ben Revere , 2B Cliff Pennington and C Carlos Perez saw their first starts of the young season, as did A's RF Mark Canha, C Josh Phegley and 2B Adam Rosales.