SAN DIEGO — The Padres are not merely playing their best baseball of the season. They’re playing some of the best baseball they’ve ever played.

San Diego thrashed Pittsburgh again on Wednesday afternoon at Petco Park, an 8-2 demolition to complete a six-game season-series sweep of the Pirates — all within a nine-day span. It marked the Padres’ 19th victory in their past 22 games — the first time in franchise history they’ve done that. A night earlier, they equaled a franchise record from 2007 by clinching an eighth straight series win.

Essentially, the Padres entered the All-Star break on the playoff bubble, and they emerged from the All-Star break as a juggernaut. Everything has gone right.

How else to explain it? In that span, they’ve made a handful of acquisitions via trade. Martín Pérez was perhaps the least notable among them. But Pérez, who arrived in San Diego with a 5.20 ERA, suddenly looks like a rotation stalwart. He’s made three starts and posted a 1.96 ERA as a Padre.

On Wednesday, Pérez dominated his former team — the team that dealt him two weeks ago for an unheralded 18-year-old prospect in the Dominican Summer League. Pérez struck out eight and walked one over 5 1/3 innings of one-run ball.

“They were my teammates for 3-4 months, but at the same time, I’ve got to go out there and do my job, because I play for the Padres now,” Pérez said. “It feels good, and it feels good to win another game.”

That’s all the Padres seem to do. With their recent hot streak, they’ve solidified themselves as clear postseason favorites and outside contenders for the National League West. As of the final out on Wednesday, they trailed the Dodgers by three games.

Of course, perhaps the craziest part of the Padres’ recent surge is that they’ve gained no ground on the Diamondbacks since the All-Star Game. They were tied then (one game above .500). They are tied now (16 games above .500).

“We see what they’re doing, and it’s obviously very impressive,” said first baseman Jake Cronenworth. “They’re playing really good right now. So are we. We’re focused on us — what we’re doing every day and what can we do to win each game.”

The Padres and D-backs are both trying to reel in the Dodgers — remarkably, the sport’s third-best team since the break. But they’re also vying against each other for the top Wild Card spot in the NL (and potentially home-field advantage in a Wild Card Series against the other).

“We’re making a run for it,” said center fielder Jackson Merrill, who had two hits and made an excellent catch in center field on Wednesday. “At the end of the day, whatever the standings are, those are the standings. ”

On Wednesday, that race between the Padres and Diamondbacks took center stage. The league’s mid-afternoon slate featured only two games, with those two teams headlining against inferior opponents.

The D-backs’ game against the Rockies started half an hour before Padres-Pirates. Arizona led 5-0 before first pitch in San Diego.

The Padres’ response was swift. Cronenworth laced a three-run homer into the Petco Porch area in right field before Pittsburgh starter Mitch Keller had recorded an out. The rout was on. David Peralta homered for the second time in as many games — on his 37th birthday, no less. Peralta, Merrill, Luis Arraez and Tyler Wade had two hits apiece.

Wade is a lightly used bench piece. Peralta will be headed back to the bench when Fernando Tatis Jr. returns from injury. Pérez is the No. 5 starter who doesn’t have an obvious place, should Yu Darvish return from the restricted list this year. And yet, the Padres continue to get big-time performances from all corners of their roster.

“We’ve talked quite a bit about getting contributions from the entire 26,” said manager Mike Shildt. “It was again on display today.”

And yet, when it was over, the Padres and Diamondbacks were again tied in the Wild Card race. They’ve played 10 times this season and split those 10 games. Their season-ending three-game series in Phoenix will decide the tiebreaker. Prior to that series, the Padres have three games against the Dodgers in Los Angeles.

It’s shaping up to be quite a finish.

“Both of those teams are playing really good,” Cronenworth said. “You see it when you look at the scoreboard in right field. It’s fun. At the end of the season, we play those two teams. It’s going to be a fun stretch.”