SAN DIEGO -- If there’s one thing that defines A.J. Preller’s tenure as Padres general manager, it’s his freewheeling nature on the trade market. No move has ever been off-limits. Preller once famously quipped that he would trade then-top-prospect Fernando Tatis Jr. if it meant he’d be getting “two Tatises” in return.

Not every Preller trade is a success story, of course. A flurry of moves early in his tenure fell flat, prompting a sooner-than-expected rebuild beginning in 2016. But lately, Preller’s hit rate has been through the roof. In the past couple of offseasons, the Padres’ general manager has made a handful of deals that, in no uncertain terms, have changed the trajectory of the franchise.

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As ever, those moves were on full display on Wednesday night in the Padres' 4-2 victory over the Pirates.

There was Yu Darvish -- acquired for Zach Davies and four prospects who ranked outside the Padres' top 10 -- tossing 5 2/3 strong innings, allowing two runs and striking out eight. Darvish, whose ERA sits at 2.27 through seven starts with the Padres, has been every bit the ace the Padres hoped he’d be. (Oh, and Victor Caratini, acquired in the very same deal, went deep on Wednesday night.)

There was Trent Grisham -- acquired along with Davies for Luis Urías and Eric Lauer -- swatting an opposite-field double to spark a sixth-inning rally. It wasn’t all that long ago that the Padres were furiously searching for a long-term answer in center field. Grisham, who also walked and is hitting .314 with a .903 OPS this season, has been that answer.

And there was Jake Cronenworth -- believed to be just a throw-in in the Tommy Pham trade that sent Hunter Renfroe and Xavier Edwards to Tampa Bay -- driving in the go-ahead runs with his sixth-inning single. The same questions Grisham answered in center field, Cronenworth has answered at second base.

That isn’t all, of course. The Padres open a three-game series with the first-place Giants in San Francisco beginning Friday night, and they’ll send Blake Snell and Joe Musgrove to the mound for the first two -- two other Preller acquisitions who are paying dividends. (Add them to the list; it’s getting awfully long.)

“Through the trades, there’s no doubt, you’re getting so many things from [Darvish] and Blake and Joe,” said Padres manager Jayce Tingler. “You’re anticipating running some aces out there, working deep into games the later the summer gets and into the fall. You expect to win those games when those guys are [pitching].”

That’s how it works. When you trade for good players, you’re liable to win more games. The Padres are 12-7 in games started by Darvish, Snell and Musgrove this season.

That trio, plus a dominant bullpen, has been the driving force behind the Padres’ 2.76 ERA, which leads the Majors. The offense, meanwhile, has underperformed, but it’s done just enough to make that excellent pitching hold up.

On Wednesday night, it was Grisham and Cronenworth who rose to the occasion. Darvish exited in the sixth after he’d allowed the Pirates to score twice to tie the game. But Grisham -- who started the game on the bench -- laced a pinch-hit double into the left-field corner. Cronenworth followed two batters later with a single over a drawn-in infield.

“We’re grinding out these wins, getting some gritty wins where you only score three or four runs,” Cronenworth said. “The bullpen’s doing a great job to keep us in these games, and the starters as well. We’ve just got to keep winning these games, and I think it’s inevitable with the guys we’ve got in this lineup that this offense is going to turn around.”

As for the trades, Cronenworth praised the Padres’ clubhouse culture for making the transition so smooth. He’s seen both sides. It was smooth for him a season ago, and he said it’s been smooth for the droves of trade acquisitions who have arrived since.

“It’s a super tight-knit group,” Cronenworth said. “We had a ton of trades at the Deadline last year, and all those guys came in, and it felt like they were on our team the entire year the first day they showed up.

“It’s been the same thing with Yu and Blake and everybody else. … They came in in Spring Training, and it’s been that seamless transition.”

It’s showing -- in the win column.