SAN DIEGO -- The Athletics added two big bats on Wednesday. They traded for Starling Marte to start the day. Then they saw Matt Chapman re-emerge.

Chapman proclaimed his return to form with a 108 mph drive off his bat in the first inning, a three-run home run that set the tone for the Athletics’ 10-4 victory over the Padres on Wednesday afternoon at Petco Park. The A’s ended a four-game losing streak and departed San Diego with a two-game split.

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Oakland (57-46) departed as a team buoyed in spirit, energized by the acquisitions of Marte and reliever Andrew Chafin this week and by the encouraging game from Chapman on Wednesday.

Now it’s on to Anaheim for four games against the Angels and a continued effort to try to hold onto the second American League Wild Card spot and perhaps improve Oakland’s postseason standing.

“We’re all excited to have two great players come to our team and help us with this last push,” Chapman said. “The end of the season is always tough. The teams that are in the hunt, they are pushing as hard as they can, adding pieces. It’s nice to know we’re getting some help, that we have two exciting guys coming to our team. We feel good about it.”

With his Statcast-projected 404-foot three-run drive to left field on an 0-1 fastball from Padres starter Blake Snell, Chapman quadrupled his RBI output for July, a month in which Oakland has gone 9-12. His only other RBI came on his only other homer of the month, Friday at Seattle.

Given a luxury of runs not seen by an A’s pitcher since Oakland beat Texas, 13-6, on June 22, left-hander Sean Manaea knew what to do. Relying heavily on his sinker and changeup, Manaea had a perfect game intact through 5 1/3 innings.

Jurickson Profar walked to end that drama, and pinch-hitter Eric Hosmer followed with a bloop single to short center field to end the no-hit bid. With the A’s holding a 10-0 lead, manager Bob Melvin turned to his bullpen in the seventh, after Manaea struck out nine and collected 15 whiffs (swings and misses) on 90 total pitches.

Manaea got through his six innings without allowing a hard-hit batted ball (95 mph or higher exit velocity). That’s a career first for him.

“These guys got me the lead in the first inning, so let’s not get too cute,” Manaea said. “Just go after guys, let the defense work and trust myself.”

Trusting himself has been a bit more challenging for Chapman, whose slash line of .221/.313/.380 remains far below career norms.

It certainly was a confidence boost for Chapman that he followed his homer by dropping an opposite-field single to right field on an 0-2 fastball from Snell in the fourth inning for his third multihit game of July. He scored three runs, matching his season high.

Both fastballs were high in the strike zone, a challenging pitch for a hitter in a funk. But Chapman crushed one and muscled the other.

“It shows that the swing I was taking today works, to get on top of those pitches and actually turn on one,” Chapman said. “I was a little out in front of the other. My swing was short today. Trust that doing that right there is enough. I don’t have to try to do too much. Just try to find the barrel, and when I do find the barrel, good things happen.”

Said Melvin: “He has the ability to be a very productive guy. He can pull the ball; he can hit the other way with power. It’s good to see him get a couple different types of hits today.”

The 10-run output was the first double-digit game for the A’s in July, a month in which they had been averaging 3.7 runs a game, 29th among the 30 MLB squads. It also allowed Chafin to make his A’s debut in a low-leverage situation, recording the final two outs.

Marte won’t be eased in, however. The plan is for him to bat at or near the top of the lineup on Thursday night.

“For us to put a lot of runs up and to keep putting consistent pressure on them, it feels good,” Chapman said. “I think it gives our team confidence. And now we’ve got another guy who’s coming to our lineup who’s hitting .300, who brings a lot of stuff to the table that we don’t have on our team at the moment. It’s just another piece to help us out.”