The A’s made it clear that their bullpen would have to play a prominent role early in the season, as starters were still not built up to pitch a full workload entering the 2020 campaign. One series in, the relief pitchers have been the stars of the show.

Five Oakland relievers combined to hold the Angels scoreless over the final five innings of Monday's 3-0 win at the Oakland Coliseum, securing a 3-1 opening-series victory over Los Angeles. The A’s bullpen was stellar over the four-game series, combining to allow just one earned run in 20 1/3 innings.

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“I don’t think they could have been better,” said Chris Bassitt, Monday's starter. “Every single guy we’ve thrown out there has been absolute nails. It’s been huge for us, because none of our starters are built up to where we need to be.

“Having every bullpen arm firing on all cylinders already is impressive, and it shows what is in store for the future once our starters get built up to go seven or eight innings. Having that depth in the 'pen is going to be insanely valuable for us down the stretch.”

Burch Smith took over for Bassitt in the fifth and got the line started with two scoreless innings. T.J. McFarland, Yusmeiro Petit and Jake Diekman followed with their own scoreless efforts, setting the bridge to Joakim Soria, who gave closer Liam Hendriks a break from ninth-inning duties and recorded his first save of the year.

The day off for Hendriks was planned, as A’s manager Bob Melvin did not want to use the right-hander after he recorded a four-out save on Sunday. That decision becomes easier when Oakland has an experienced arm like the 36-year-old Soria, who in his 13th Major League season now owns 222 saves, the most by a Mexican-born pitcher.

“We did things a little differently with Hendriks down,” Melvin said. “I didn’t really want to pitch Soria either today, but he wanted the ball in the ninth. That’s why you have these veteran guys to pitch in these position. We had to use our bullpen quite a bit this series, but it ends up being three out of four. That’s huge for us.”

And the offense responded when called upon. After recording just one hit through the first three games of the season, Matt Chapman broke out with three hits on Monday, including a booming third-inning RBI double of Angels starter Griffin Canning. Mark Canha later added to the A’s lead with a solo blast off Canning in the fourth that was smoked at 104.5 mph off the bat and landed in the left-field bleachers a Statcast-projected 425 feet from home plate.

Chapman felt he was pressing a bit in his at-bats over the weekend, though he also gave credit to the Angels' pitchers, who know him well from divisional matchups. On Monday, Chapman was back to his hard-hitting ways, recording an exit velocity of 102 mph or better on two of his three hits.

“I’m definitely getting more and more comfortable,” he said. “That first game I felt like I hit hard balls right at guys, and the second and third game maybe tried to do a little too much. ... I had to try to get back to what I was trying to do and just make sure I was on time with the pitches.”

Bassitt held the Angels scoreless over four innings in his first start of the regular season, recording five strikeouts, including two swinging punchouts of superstar Mike Trout. The right-hander ended his outing with a heads-up play on the mound, escaping a bases-loaded jam on a comeback that he turned into a 1-2-3 inning-ending double play that kept the momentum on the A’s side.

With a strict workload set at a 70-pitch limit, Bassitt finished the outing at 66 pitches. He’s expected to increase that count to around 85-90 pitches in his next start.

"He was great,” Melvin said. “He was a little tired, had to work hard a couple of innings. But when he takes the mound, we feel great.”

In a shortened 60-game campaign, the A’s are looking to buck their trend of slow starts. Entering Summer Camp with an emphasis of coming out strong, Oakland taking three of four in its first series is certainly a good first step -- the club is 3-1 to start a season for the first time since 2010.

“Every game is more important now, and you don’t have much of an opportunity to make up time,” Chapman said. “We were trying to put an emphasis on getting off to a good start, but we don’t want to put extra pressure. We’re still taking it day to day. The best way to have success is not to put pressure, but we needed these wins.”