OAKLAND -- The A’s called up Seth Brown hoping he could just hold down the fort in the absence of Stephen Piscotty. Just eight games into his Major League career, Brown has surpassed those expectations, positioning himself as an unlikely hero down the playoff stretch.

The rookie outfielder drew another start in left field Tuesday and wasted no time endearing himself to the Coliseum faithful in his first game in Oakland in a 7-5 win over the Angels. Brown tied an Oakland single-game record with two triples, including a go-ahead three-bagger off Noe Ramirez in the sixth that put the A’s on top for good. The victory moved the A’s into a tie with Cleveland for the second American League Wild Card.

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“It was fantastic tonight. It’s hard to describe,” Brown said. “It was my first time in the Coliseum tonight, so it was just an unbelievable moment and an unbelievable night. It’s something I’ll never forget.”

Brown became the first A’s rookie to record two triples in a game since Mark Ellis on Aug. 3, 2002, and the first A’s player since Matt Chapman, who accomplished the feat last year in a road game against the Rangers on July 26.

The results have come immediately for Brown, who recorded two hits and an RBI in his Major League debut at Kauffman Stadium last week. Through his first eight career games, Brown is now 13-for-29 with nine RBIs.

“I think the thing that impresses me the most is how confident he is. He’s pretty tenacious,” A’s manager Bob Melvin said. “For a guy that first comes to the big leagues, a lot of times you don’t see that. Now, when you’re hitting .480 or whatever he’s hitting, it’s easy to be confident. But he had to get to this point. We saw it right away in Kansas City. He’s in the big leagues now and he’s looking to stay. He’s taking advantage of his opportunity.”

It hasn’t just been Brown’s offense that has impressed the A’s, the left-handed outfielder also showed off his arm by nabbing Justin Upton as he tried to go from first to third on a single by Andrelton Simmons in the second, recording his second Major League assist.

• Brown impresses A's with defense against KC

The out at third base helped A’s starter Mike Fiers, who picked up a no-decision after allowing four runs over five innings, to limit the damage to just one run in that second frame.

“It’s a small sample size, but he looks great,” Fiers said. “He’s throwing guys out and doing everything right. He’s come in at the right time and picked us up.”

With Ramón Laureano set to return from the injured list over the weekend, it’s unclear if Brown will continue starting games on a regular basis. For now, he’s making his best case to remain in the lineup for the foreseeable future.

“We've got some time. It seems like things play out a lot of times before you get to that point,” Melvin said. “But he’s worthy of the playing time he’s getting right now, and I don’t see that slowing down at this point.”

Petit comes up clutch

The A’s were on red alert in the sixth. Blake Treinen had already surrendered the lead by allowing a game-tying solo blast to Justin Upton, and the Angels were threatening to take the lead with runners at first and second with two outs. In comes Yusmeiro Petit.

Melvin has leaned on Petit to put out the fire often this season, and the right-hander came through again as he induced a popout against David Fletcher to end the threat.

The two runners stranded in the sixth brought his inherited runners stranded total to a Majors-leading 42, but he wasn’t done there. After Brown’s RBI triple highlighted a two-run bottom of the sixth, Petit came back out and shut the door on the Angels with a 1-2-3 seventh against Mike Trout, Shohei Ohtani and Albert Pujols.

“He gets the biggest out with guys on base and then faces the middle of the order. He’s been doing it all year,” Melvin said of Petit. “Every now and then, you get the soft part of the lineup, but he very rarely does. He leads the league in appearances by four or five now and is one-plus every time he goes out there. One of the top relievers in baseball, for sure.”

Closing in on history

Chapman’s go-ahead three-run blast off Angels starter Jaime Barria in the third was his 31st homer of the season, tying him with Sal Bando for second-most by a third baseman in A’s history. Chapman is one away from Eric Chavez, who hit 32 in 2001.

Like most of his home runs, Chapman’s blast was a no-doubter, hit at 106.1 mph off the bat and smacking off the "Holy Toledo" sign in dead center for a projected 410 feet, according to Statcast. The All-Star third baseman now has 42 extra-base hits that have registered at least 105 mph off the bat, trailing only Trout (45) and Pete Alonso (51) for most in the Majors.