As the Padres set out to upgrade their big league roster at the Trade Deadline, they went to great lengths to keep catching prospect Luis Campusano on board.

Sure, rival general managers asked about him -- why wouldn't they? Campusano is a serious power threat who was named co-MVP of the Class A Advanced California League last season, hitting .325/.396/.509. Oh, and he's a solid defensively, too.

General manager A.J. Preller had bigger plans for Campusano. Preller swung six trades before the Deadline, none of which included Campusano. Then, four days after the Deadline, the 21-year-old catcher got his big league callup -- and rewarded his GM’s faith.

Campusano, the Padres’ No. 4 prospect and No. 52 overall, according to MLB Pipeline, added the extra point on a 7-0 Padres victory in Oakland on Friday night. With San Diego leading by six in the eighth inning, Campusano launched an opposite-field home run in his big league debut for his first career hit.

• What to expect from Campusano in Majors

“He's crazy strong,” said Padres manager Jayce Tingler. “... You watch his BP, the ball just has a different sound off the bat. Being able to go oppo, to see him smile and know he got that first hit and that first homer out of the way -- now he can relax and play.”

Campusano became the 15th player in Padres history to hit a home run as his first Major League hit. He’s the first to do so since Patrick Kivlehan in 2016.

The Padres selected Campusano in the second round of the 2017 Draft, and he has raked at every level. Still, the callup Friday came as a minor surprise, given that Campusano had never played a game above Class A Advanced.

“We were in the Minor Leagues together, and now we're here in the big leagues together,” said shortstop Fernando Tatis Jr. “It's great to see a guy coming up from the farm system and helping the team over here.”

According to those in attendance at the University of San Diego (the Padres' alternate training site), Campusano has been on a home run binge for about a month. He joins a catching mix that already includes newcomers Austin Nola and Jason Castro.

“They're all going to catch,” Tingler said. “They're all going to play. We're going to keep them sharp. We're going to keep them fresh. All three guys are going to catch and get at-bats.”

The Padres called up Campusano mostly because of his potent righty bat, and he served as the designated hitter on Friday against left-hander Jesús Luzardo. Campusano posted a 1.072 OPS vs. left-handed pitching last season, and the A’s send another southpaw, Sean Manaea, to the mound on Saturday.

The Padres already boast arguably the best offense in baseball this season, but it's easy to see how Campusano's presence balances things out against left-handed pitching. He can platoon with the lefty-hitting Mitch Moreland in the DH spot. Or, if Campusano catches, the versatile Nola could take the place of, say, lefty-hitting second baseman Jake Cronenworth.

Cronenworth, the National League Rookie of the Year Award favorite, and right-hander Luis Patiño are already difference-making rookies in San Diego. Although the Padres moved 16 players at the Deadline, their farm system remains strong.

“We still feel like we have one of the better farm systems, if not the top farm system, in the game,” Preller said earlier this week. “We feel like, ultimately, we have a lot of players, not just at the very top of the system. More waves coming, here in the next couple years, in the next couple months."

He wasn’t kidding. On Friday night, Campusano became the latest Padres rookie to join the fray.

Perdomo to IL
The Padres placed right-hander Luis Perdomo on the injured list with right forearm inflammation. In nine appearances this season Perdomo owns a 5.06 ERA.

To clear room on the 40-man roster for Campusano, the club moved left-hander José Castillo to the 45-day IL. That move was merely procedural and doesn't change the team's hopes that Castillo might return later this month.

The Padres’ bullpen, of course, has already received a boost this week with the additions of Trevor Rosenthal and Dan Altavilla.

Tatis leads off again
With Trent Grisham slumping -- and with the Padres facing left-hander Jesús Luzardo -- manager Jayce Tingler returned Fernando Tatis Jr. to the top spot in the lineup Friday. Grisham, who batted leadoff in 16 consecutive starts, hit ninth.

In essence, Grisham is still setting the table for Tatis, but he's also getting one fewer at-bat against Luzardo. Grisham is hitting just .184/.225/.263 against lefties this season, and he has slumped to a .154 average over the past week.

“We all go through pockets of the year where you’re going to struggle,” Tingler said. “That’s how this game’s built. … Hopefully we get it turned around quick. Grish has been a huge part of what we’ve been able to do so far, offensively and defensively.”

As for Tatis, he entered play Friday batting .301/.370/.663 in the leadoff spot this year.