SEATTLE -- It took 21 years for the Mariners to bring postseason baseball back to Seattle. After George Kirby left the mound to a hero's roar at the end of the seventh inning, it took what felt like another 21 years to finish.

Kirby’s brilliance was long forgotten by the time Houston’s Jeremy Peña homered in the 18th inning, breaking the longest scoreless tie in MLB postseason history to give the Astros a 1-0 win. What once looked like a defining outing -- a young star announcing himself to the baseball world -- was erased by six hours and 22 minutes of exhausting, exhilarating, record-setting baseball.

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That’s why this ALDS loss to the Astros, a 3-0 sweep, is so heartbreaking. It’s also why Mariners fans can collapse into bed Saturday night confident that this club is set up with a loaded young rotation for years to come.

“I thought our pitching was just off the charts, starting with George Kirby,” said manager Scott Servais. “To fire him out in a must-win game and you get seven shutout innings out of a rookie against that club? You can't ask for any more. I thought he was outstanding. He commanded and was in total control. It’s great experience. … It is going to benefit us just immensely going forward.”

This was a masterclass of pitching, with 42 strikeouts between the two clubs and Herculean efforts from both bullpens. The starters set the tone, though, with Lance McCullers Jr. on one side and Kirby on the other, getting better as the night went on. 

Aces are born on the final pitch of an outing, but that door often needs to be opened for a young pitcher from the other side. Kirby’s moment came in the top of the seventh, with two runners on, two out and Jose Altuve coming to the plate. With Andrés Muñoz warming in the bullpen, Servais had a word with pitching coach Pete Woodworth and started to climb the dugout steps. Then he stopped.

The Mariners let the kid face one of the decade’s most decorated hitters, and with his very last pitch, Kirby beat him. It was a high fastball -- shoulder-level on Altuve -- clocked at 97.7 mph. Kirby’s 92nd and final pitch was the second-hardest he threw all afternoon. Kirby, typically stoic on the mound, clenched his fists across his chest and howled. He’d earned this moment.

"He was unbelievable,” said catcher Cal Raleigh, who had the best seat in the house. “To go out and throw seven scoreless against the Houston Astros -- as a rookie -- the man is super special. I'm super excited to see what he can do in the future. I feel like he's only just scratching the surface right now."

Thoughts of 2023 won’t ease the pain from Saturday’s loss. Whenever the time comes to shift an eye to next year, though, the Mariners profile as one of the better rotations in baseball, pitching in front of a talented bullpen. Alongside Kirby, Seattle has ace Luis Castillo, who dazzled in the postseason with a rare combination of velocity and movement, and just inked a new five-year extension.

Then there’s young Logan Gilbert, who would have started a Game 4, and Robbie Ray, with four years remaining on his deal. Look further and you’ll find No. 2 prospect Emerson Hancock, No. 5 Bryce Miller and No. 7 Taylor Dollard, all coming off stellar years at Double-A Arkansas with bright futures. The Mariners can pitch today, and they’ll sure be able to pitch tomorrow.

“I’m super proud of those guys,” Ray said. “I mean, the pitching is the reason we're here. And they were a huge part of that. I didn't know a whole lot about them because Spring Training kind of jumped on us after the lockout, but just seeing those guys from Spring Training until now, I mean … They're men now."

Kirby lets his game do the talking. He knows this group can be special, and for that to happen, he’ll need to be at the forefront. Changes will come this offseason -- all steps forward, the Mariners hope -- as they enter the sweet spot where young stars are paired with established veterans.

“We did great all year,” Kirby said. “Dominate the zone -- that’s the name of the game here. Get ahead and you’ll do well. First strikes and you’ll do well. I’m just glad that we fought to the end. Everyone played a huge part in this.”

Now the wait begins. Questions will come, like how the Mariners can ever beat the Astros, or how they failed to scrape a run across for 18 innings. The foundation of this roster is pitching, though, and it’s been years since this organization stood on such solid ground.