SEATTLE -- This penultimate day of the regular season was always going to be a headache for the Mariners.

When the revised schedule was released after the lockout was lifted in March -- which resulted in a delayed start and finish to the regular season -- manager Scott Servais had a hunch that a nine-day stretch with 10 games leading into a hopeful postseason appearance would hamper his roster, particularly pitching-wise.

Such was the precise case in a 7-6, 10-inning win over the Tigers in the opener of Tuesday's doubleheader at T-Mobile Park, which forced Servais to use catcher Luis Torrens on the mound once the game reached extras. Thankfully for Servais, Abraham Toro ended it in the 10th with a sacrifice fly to score Carlos Santana, who had just previously ripped a game-tying RBI single to score automatic runner Eugenio Suárez.

Torrens, who allowed only one unearned run while on the mound in the 10th, became the first position player in Mariners history to record a pitching win.

Then, in a 9-6 win in the nightcap, Justus Sheffield gave Servais 99 pitches over five innings to help cover as the 29th man appointed to the roster for the doubleheader.

Aside from the stress of mapping out arms, the victories gave the Mariners some clarity on their postseason destination, which will be Toronto for the American League Wild Card Series beginning Friday. With Tampa Bay’s rain-shortened 6-0 loss in Boston, the Mariners locked up the No. 5 seed, one day after the Blue Jays secured the No. 4 seed and home-field advantage for the best-of-three series.

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The Mariners were eliminated from the chance of hosting the Wild Card Series at T-Mobile Park on Monday, and their only chance for home postseason games will be to advance past the Blue Jays to the AL Division Series -- where the AL West juggernaut Astros will await. Games 1 and 2 of that best-of-five series will be played at Minute Maid Park, and the first opportunity for a postseason game in Seattle would be Game 3 on Oct. 15.

But first, the Mariners have to get there -- and it began with an all-hands-on-deck effort Tuesday, which will continue into the regular-season finale on Wednesday, with pitching preservation squarely at the forefront of mind.

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“This is about putting us in the best position to win a playoff series,” Servais said of Tuesday's strategy. “And again, I think you guys know how competitive I am. I want to win every game. But it's about playing the long game here, getting us to that point. So the decisions today are going to be a little clunky.”

Marco Gonzales is slated to start Wednesday vs. the Tigers and will completely empty the tank to spell as many bullpen arms as possible. As such, Gonzales is not expected to be on Seattle’s Wild Card Series roster, because the soonest he’d be available on regular rest would be Monday, at which point the series will be over. The Mariners are permitted to adjust their roster after each round.

Gonzales is more stretched out and will likely be available to throw 100 pitches, a threshold Servais said he’d avoid with the other starters in this final turn. It's well beyond the capacity of Chris Flexen, who had a shorter leash given that he was making his first start since Aug. 6 when he took the mound for the twin-bill opener.

Flexen, who was admittedly “gassed” by the end of his four innings, allowed three runs (including a two-run homer to Spencer Torkelson), but he achieved precisely what the Mariners hoped.

It’s also why Sheffield was recalled from Triple-A Tacoma and made his first big league appearance since June 18, as well as why Torrens was used once the first game reached extras.

Per MLB rules, position players are only permitted to pitch in games in which a team has a six-run lead or deficit, or in extra-inning contests, unless the player has a two-way designation, such as Angels two-way star Shohei Ohtani.

Servais hinted Tuesday morning that folks tuning into the doubleheader would “see some very unconventional things happen” with Seattle’s pitching, which is exactly what manifested.

“It was always going to be a challenge,” Servais said. “I think any manager's worst nightmare is when you run out of pitching when you have it mapped out, and sure enough, that's what we looked at today.”

The Mariners made it through the twin bill mostly unscathed, other than utility man Dylan Moore being hit by a 93.2 mph fastball with the bases loaded in the sixth inning of the nightcap. The moment was a scare, especially after Seattle’s other top bench player, Sam Haggerty, was placed on the 10-day injured list earlier Tuesday with a left groin strain that will cause him to miss the first two rounds of the postseason.

Moore was later pulled, underwent X-rays that were negative and should be fine. But it was a microcosmic moment of simply getting to the finish line healthy -- and there’s still one game to clear.