New York Mets shortstop Francisco Lindor misses the catch as...

New York Mets shortstop Francisco Lindor misses the catch as the Padres' Xander Bogaerts reaches first base in the eighth inning on Saturday in San Diego. Credit: AP/Gregory Bull

SAN DIEGO — With a 3-1 loss to the Padres on Saturday night, the Mets had their winning streak end at a season-best six games. On a blah night, they fell victim to a superb start by lefthander Blake Snell, who might be the hottest pitcher in baseball.

Of the 27 outs made by the Mets, a season-high 17 came on strikeouts. Francisco Lindor led off the ninth with a single but did not advance past first base.

Perhaps more interesting than any of the above, though, is what it sets up for Sunday: a huge swing game.

The series finale also is the first-half finale. “Of course there is” value in carrying positive momentum into the All-Star break and four days off, manager Buck Showalter said at the start of the weekend. A lot of that will be on the line when Max Scherzer faces off against Joe Musgrove.

If the Mets win, it would mean taking a third straight series (after not winning any for a month) as well as seven victories in their past eight games — a heck of a rebound to reinsert themselves into the wild-card discussion.

If the Mets lose, it would mean dropping two of their last three games and thus the series, plus losing out on the head-to-head-record tiebreaker for the playoffs (in the event that matters come season’s end). The Mets lead the season series 3-2.

The Padres, also a big-money, big-talent team that has not played to expectations, will face similar stakes. The clubs are 42-47 and even in the wild-card race, 6 1⁄2 games out of the last berth (held by the Phillies).

“That would be great — go into the All-Star break feeling good,” Mark Canha said. “Both teams are probably on the same page there. We want to win this series. We’ve been playing good baseball. We like where we’re at. To be feeling good about ourselves going into the break, it would be huge.”

Showalter said: “It would be a good way to end this time before we take a break.”

Lindor, who has been sharp at shortstop all season, had a weirdly bad night, committing two errors and making a couple of other odd plays. “It makes you realize what an unbelievable level he’s playing at when it sticks out that much,” Showalter said. “I and we don’t think twice about it.”

Francisco Alvarez provided the Mets’ lone run with a solo home run in the seventh, a continuation of his hot hitting. He has homered in four of the five games on this road trip. In the other game, he had four hits.

Alvarez’s 17 homers are the second-most among catchers in an age-21-or-younger season. Atop the list: Hall of Famer Johnny Bench, who hit 26 in 1969.

Snell struck out seven of his first eight batters on the way to 11 total. He allowed one hit in six scoreless innings. In his past eight starts, he has a 0.56 ERA and 78 strikeouts in 48 innings.

“The way he’s been pitching lately, it was one of those nights tonight when you have to go down and pick a good pitch, which is hard to do because his stuff moves a lot and it’s explosive,” Canha said. “And you have to hit a good pitch, which is a whole other thing.”

Nick Martinez and Josh Hader struck out five Mets in the final two innings.

David Peterson yielded three runs and five hits in 5 1⁄3 innings. He struck out seven and walked two. His final line would have looked much better if not for a messy three-run second frame. Matthew Batten, a rookie taking his first major-league at-bat of the season (after a cameo last year), had the big blow, a two-run home run to leftfield.

Peterson has a 2.35 ERA in three starts since returning from Triple-A Syracuse. His rotation spot is in question with Jose Quintana due back for his Mets debut after the break.

“I felt like I was able to go after them with every weapon that I have,” Peterson said. “It just came down to a couple of pitches. And that was on me.”

Now the Mets, who typically espouse one-day-at-a-time, each-game-is-the-same cliches, will play Sunday in a contest they admit they want more than usual.

“You want to feel good about yourself and where the team is at going into the break, stay on the winning train that we’ve been on,” Canha said. “We’ve been playing well. You want to keep that momentum going. We need to keep that momentum going.”

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