SAN DIEGO -- The resurgent Mets reached the All-Star break with a renewed sense of purpose and promise, thanks to a winning road trip.

But they won’t go into it with three consecutive series wins after falling, 6-2, to the Padres on Sunday afternoon at Petco Park.

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New York tied a bow on its 4-2 excursion with a shaky performance from Max Scherzer and an offense that for the second straight contest was mostly underwhelming. But even in the loss, the Mets showed their grit. Down 6-0 in the eighth inning, they reached for their bats instead of a white flag.

Luis Guillorme opened with a double and Brandon Nimmo coaxed a walk out of reliever Adrian Morejon. Mark Canha then smoked a two-run double.

Suddenly it was 6-2, Canha was in scoring position, and Morejon hadn’t recorded an out.

With New York’s big bats coming up, just maybe some late-inning magic was in the San Diego sunshine for a team that was 6-1 in July.

But Francisco Lindor grounded out and shortstop Xander Bogaerts made a nice leaping catch of Pete Alonso’s liner, with Canha being tardy returning to second. He was doubled up and the Mets were down to their last three outs.

But New York went quietly and now seeks to make some noise in the season’s final three months. Nimmo said the squad that recently left New York has a different mojo after its swing through Arizona and San Diego.

“[It was] this West Coast trip, honestly,’’ Nimmo said. “I think we did pretty good going into Arizona and sweeping those guys, and it was a hard-fought game on Friday and we came out on top. I think there are a lot of things in the last week that you can look at that are very positive.’’

Manny Machado put the Padres ahead, 3-0, in the first inning as he smacked the first of two home runs. Scherzer’s 85 mph slider got too much of the plate, and Machado redirected it into the second deck of the Western Metal Supply Co. building in left field.

“I’ve got to be better than that,’’ Scherzer said. “I had a chance to get out of the inning, and I didn’t. I’m executing the slider at times, and it is good. And at times, it is bad. That’s the worst thing you can have, an inconsistent pitch. I’m leaving it in the middle part of the plate at the wrong time.’’

The Mets had an opportunity to climb back into the game in the fourth.

Lindor singled before Joe Musgrove plunked Alonso and Jeff McNeil to load the bases. But Musgrove dug in and fanned DJ Stewart and Francisco Alvarez to squash the rally.

“We had a couple of spots where we could have got into it with the bases loaded,’’ manager Buck Showalter said. “But we couldn’t get that knock.”

Unfortunately for the Mets, Machado wasn’t done flexing his muscles.

After Fernando Tatis Jr.’s one-out single in the fifth, Machado went deep again for his third home run in the series, giving him five RBIs in the game. That increased the Padres’ advantage to 5-0.

That was Scherzer’s last frame, his day done after five innings. He was touched for five runs on six hits and three walks, while striking out seven.

Still, the Mets have turned the narrative around from being an underperforming bunch to a group that could be a factor once the Midsummer Classic is complete. New York delivered a great start to July and now has some concrete results to match its unwavering confidence.

Improving its record in rubber games of series to 5-7 would have been a boost. But to Showalter, there’s no shame in getting beat by Musgrove -- and the night before, Blake Snell. 

“I think it was two really good pitchers on the top of their games,’’ the manager said. “... We’ll start fresh against the Dodgers. We’ll put it behind us and tip our hat to some good pitchers.’’