OAKLAND -- Third baseman Brett Harris fielded a one-hopper and threw to first to record the game's final out -- and the A's hope it's the first of many wins Harris will be involved in.

Harris, the A’s No. 9 prospect according to MLB Pipeline, made his Major League debut in Friday's 3-1 win over the Marlins.

“I want the ball at all times,” Harris said. “Bases loaded, doesn’t matter. I want the ball. I trust myself to help the pitcher out. I’ll always want the ball.”

The 25-year-old defensive wizard had three balls hit to him and fielded them cleanly.

While he was solid defensively, he finished his debut still waiting for his first hit. Batting ninth, Harris went 0-for-3 with two strikeouts.

He was late on a fastball and flied out to right on his first at-bat in the third. He came up again with a runner on third and one out in the fifth, but swung through three changeups. He struck out on a sinker in the seventh to end his night at the plate.

“You've got to start somewhere,” Harris said. “Just build off today and move on.”

Harris was originally selected by the A’s in the seventh round of the 2021 MLB Draft, and joins fellow draftees Zack Gelof and Mason Miller in Oakland. He has hit .281 with 32 home runs, 159 RBIs and an .825 OPS in 272 Minor League games, but is mostly known for his skills with the glove.

After Harris took ground balls before Thursday’s game with Triple-A Las Vegas, Aviators manager Fran Riordan told him to look up at the scoreboard, where he saw a message: “Brett Harris to the Show.”

His parents Kerri and Lance and his fiancée Sydney were able to attend his debut in Oakland, along with some childhood friends from Chicago -- some of whom took the red-eye home so they could get back to work on Saturday.

“Obviously, it’s something you dream of since you’re playing in the backyard,” Harris said. “It’s pretty surreal. I think once I get back to the hotel I’ll try to wrap my head around it. Right now I’m enjoying a good win, which makes the debut more memorable.”

Harris' cheering section also watched JP Sears throw 6 1/3 scoreless innings and Brent Rooker hit a two-run homer in the fourth inning as the A’s (16-17) extended their season-best winning streak to five games. Miami had its three-game winning streak snapped.

Sears worked around a one-out triple in the second inning and a leadoff double in the third inning. Lucas Erceg struck out Tim Anderson with the bases loaded and two outs in the eighth inning.

Erceg allowed a run with two outs in the ninth inning, ending an extended scoreless streak from the A's bullpen, which fell one out short of tying the Oakland record of 30 innings, set in August of 2020.

With a runner on second, Erceg got Jesús Sánchez to ground out to Harris to end the game and put a cap on an eventful day for the young prospect.

“Brett’s a kid that we looked at in Spring Training,” manager Mark Kotsay said before Friday's game. “Had a really good season last year, saw him in the Fall League, plus defender, his bat will play, has some power but he has a really good eye, really good zone discipline. This is his opportunity to go out and take advantage of this.”

After splitting time last season between Double-A Midland and Triple-A Las Vegas, Harris spent this season exclusively in Las Vegas, where he started 21 of his 26 games at third base and hit .289/.418/456.

“I have to remind myself it’s the same game," Harris said of his mindset anticipating his debut. "Pitchers, same distance away. Bases are still the same distance away. It's just a bigger stadium. I don’t know how to put it into words, but I’m very excited to be here and help this team win any way I can.”

Before the game, the A’s also reinstated infielder J.D. Davis from the 10-day injured list. Davis started at first base and hit fifth in Friday's opener after Ryan Noda was sent down to Triple-A on Wednesday.

To clear space on the active roster, shortstop Nick Allen was optioned to Las Vegas after hitting .171/.227/.243 in 70 at-bats. To free up a spot on the 40-man roster, Freddy Tarnok (right hip inflammation) was transferred to the 60-day injured list.

“It’s a reset for Nick and Ryan,” Kotsay said. “We’re a month into the season, and offensively they’ve had a challenging time for these first 100 at-bats, and it’s time to go down, build some confidence, start performing, start getting their swing. There’s a place for them here, but the timing is to get them out and get their bats going.”