Detroit Tigers reliever Jason Foley hung a second-pitch slider to Fernando Tatis Jr. with a runner in scoring position and two outs in the bottom of the 10th inning.

That small mistake made a difference.

The Tigers lost, 6-5, to the San Diego Padres on Wednesday on a walk-off single from Tatis, who recently returned from the injured list, in the second of three games in the series at Petco Park.

The game ended when Tatis, a right-handed hitter, smacked the right-handed Foley’s middle-middle slider on the ground and through the left side of the infield, enough to score the free runner in extra innings from second base.

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“We had our chances,” manager A.J. Hinch told reporters in San Diego. “We were chipping away, which got us the lead, and then they showed their quick-strike offense and shut-down bullpen. Tough game and a tough loss, especially getting into extra innings. We didn’t do anything with our extra runner. They were able to push theirs across.”

The Tigers (70-70) — following back-to-back losses — dropped to 5½ games back for the third and final spot in the American League wild-card race. Three AL teams are at 70-70: the Tigers, the Boston Red Sox and the Seattle Mariners, with the Tampa Bay Rays at 69-70.

Right-hander starter Keider Montero, who has a 5.47 ERA through 14 games in his rookie campaign, squandered a five-run lead by allowing the Padres to score five runs across the fourth and fifth innings.

Battle of bullpens

The Padres missed opportunities with the bases loaded in the sixth and seventh innings, stranding all three runners against right-handed reliever Beau Brieske in the sixth and right-handed reliever Shelby Miller in the seventh.

Meanwhile, right-handed reliever Will Vest made his job look easy against the Padres’ three best hitters — Tatis (swinging strikeout), Jurickson Profar (swinging strikeout) and Manny Machado (groundout) — in the eighth. Vest then returned for the ninth and retired three batters in a row to send the game to extra innings.

In the top of the 10th, the Tigers had runners on the corners with two outs against right-handed reliever Jeremiah Estrada, but right-handed Justyn-Henry Malloy, pinch-hitting for lefty Andy Ibáñez, flew out to center to end the inning.

The Padres walked-off the Tigers in the 10th. Before Tatis’ walk-off single, the Tigers intentionally walked contact-first left-handed hitter Luis Arraez, who wasn’t a favorable matchup because Foley historically struggles against lefties.

Also, Foley doesn’t miss bats.

“We’ll take our shot with a righty,” Hinch said. “I thought the ball could get on the ground, which it did, but you’re not in a good spot either way. We thought the better shot at getting the ball on the ground at somebody was going to be with the righty.”

Tatis, whose walk-off single ended the game, returned from the injured list before Monday’s series opener against the Tigers. He hadn’t played since June 21 because of a right femoral stress reaction.

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Keider Montero’s start

Montero fell apart in the fourth inning.

Walking Xander Bogaerts put two runners on with one out for rookie Jackson Merrill, who collected his 22nd home run in his 136th game. He hit Montero’s middle-middle fastball for a three-run home run to left-center, cutting the Tigers’ lead to 5-3.

In the fifth inning, the Padres jumped Montero with back-to-back hits from Arraez (single) and Tatis (double) to put runners on the corners. Both hits occurred on pitches that Montero left over the middle of the strike zone.

With one out, Machado — the final batter of Montero’s start, regardless of the outcome — got just enough of a down-and-away changeup in a two-strike count, producing a ground-ball single to tie the game at 5-5.

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Montero, 24, allowed five runs on seven hits with two walks and two strikeouts across 4⅓ innings, throwing 71 pitches. He has surrendered at least four runs in eight of his 14 games since making his MLB debut in late May.

Yu Darvish’s start

Right-hander Yu Darvish, a five-time All-Star, was placed on the restricted list in early July while tending to a personal matter. The 38-year-old made his long-awaited return Thursday against the Tigers, but he wasn’t sharp.

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The Tigers worked Darvish for numerous deep counts, forcing his exit after 63 pitches in the third inning. He allowed three runs on four hits and two walks with four strikeouts across 2⅔ innings.

Matt Vierling put the Tigers ahead, 1-0, when he turned on an up-and-in 95 mph fastball with two strikes and two outs in the first inning. It was his 16th homer of the season.

The Tigers extended their lead to 2-0 in the second inning, thanks to a leadoff walk from Spencer Torkelson. He came around to score on a single from Jace Jung, a wild pitch by Darvish and an RBI groundout from Dillon Dingler.

A leadoff walk from Riley Greene created another scoring opportunity in the third inning, which the Tigers took advantage of with Colt Keith’s two-out RBI single for a 3-0 lead. The single from Keith, who had been slumping for the past week, chased Darvish.

Facing left-handed reliever Yuki Matsui, rookie shortstop Trey Sweeney put the Tigers ahead, 5-0, in the fourth inning with a two-run home run on an up-and-in fastball with two strikes. Jung, a fellow left-handed hitter, kickstarted the run-scoring inning by working a leadoff walk, just like Torkelson in the second and Greene in the third.

It was Sweeney’s first home run against a left-handed pitcher in the 2024 season, following 15 homers in 107 games in Triple-A and two homers in 15 games in MLB.

Contact Evan Petzold at epetzold@freepress.com or follow him @EvanPetzold.

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