SEATTLE -- The better at-bats to watch in Major League Baseball are those pitting the best pitchers against the best hitters. It’s an objective, albeit obvious, take.

But the best at-bats in the Majors are those in which the opponents deliver on those high-stakes showdowns and the audience comes away appreciating both sides even more than they already did, regardless of the outcome of the battle.

Such was the scene in sun-soaked Seattle on Thursday, when José Ramírez stepped to the plate representing the go-ahead run with two outs in the top of the eighth inning. Not risking potentially fateful damage, Mariners manager Scott Servais turned to his best arm, flamethrower Andrés Muñoz, who despite being in his first full season has emerged as one of the game’s top high-leverage relievers.

For Mariners fans salivating for a playoff chase, it was grab-your-popcorn, call-your-neighbors, edge-of-your-seat material.

Over two-ish tense minutes, Muñoz won a critical, seven-pitch strikeout against J-Ram that halted Cleveland’s rally, leaving all who watched in awe. Then, Muñoz came back for a 1-2-3 ninth inning with two more punchouts to seal a 3-1 win that began a critical four-game set between these postseason hopefuls. More on the epic matchup momentarily.

Marco Gonzales was also brilliant, overcoming some hard contact in the first inning and retiring 16 of his final 18 batters. Mitch Haniger backed him by crushing a decisive three-run homer off Triston McKenzie in the first, bringing his slash line to .313/.378/.507 (.885 OPS) since returning from the IL on Aug. 6.

If the season ended Thursday, the Mariners would visit the Guardians for the best-of-three Wild Card Series as the No. 6 and 3 playoff seeds, respectively. And given how tight Thursday’s tilt was -- especially encapsulated in those Muñoz vs. Ramírez moments -- it had the recipe of a possible postseason preview.

“If you want to win the games against the best teams,” Mariners manager Scott Servais said, “you’ve got to get the best hitters out at the most critical times.”

Muñoz continues to show remarkable poise in big moments, with Ramírez the latest elite slugger to become a strikeout victim. Others include Shohei Ohtani, Mike Trout, Jose Altuve, Yordan Alvarez, Pete Alonso, Vladimir Guerrero Jr., Carlos Correa and more.

It underscores how far he’s come since a May 22 outing in Boston when he surrendered a walk-off grand slam. In 35 outings since, including Thursday, he’s held hitters to a .145/.201/.218 (.419 OPS) slash line and has a 1.19 ERA and 45.5% strikeout rate, MLB’s second-highest to only Edwin Díaz.

His season-long progression was all encapsulated in one epic duel:

• Ramírez thrives in these moments, entering play with a .959 OPS in high-leverage situations and 103 RBIs, second to only Aaron Judge. It was his time to shine, and Muñoz quickly fell behind 2-0 on sliders outside, putting Ramírez in a hitter's count. But Muñoz opted to stay with the breaking ball when Ramírez was thinking heater, generating a big whiff. Strike one.

• Muñoz stuck with the slider, but Ramírez timed him up just early, yanking the pitch on the lower black into foul territory down the right-field line. Had he been a little more on time, it would’ve reached the corner and easily scored two. Strike two.

• Now it was time for the 101.5 mph heater, which Muñoz threw high and away, but Ramírez fouled it off to stay alive. Then came arguably the wildest pitch of the day, when Muñoz back-footed a slider that Ramírez -- somehow, some way -- made contact with. Yet Muñoz stuck with his instincts and dialed up his hardest slider yet, at 91.4 mph, and got Ramírez to swing over the top. Strike three.

“I’m just trying to do my job and just trying to fool Ramírez, and he was just doing his job putting the ball in play,” Muñoz said through an interpreter. “It was just a matter of time in a cat-and-mouse game.”

What did the other dugout think?

“I saw 102 and then a slider -- that was pretty filthy stuff,” Guardians manager Terry Francona said. “I don’t think you have to be in the game 40 years to know that was pretty special stuff.”

The Mariners advanced to 54-2 in games in which they lead after eight innings. In another quirk, Thursday’s game was the first of the season in which both teams scored in the first inning but didn’t plate any the rest of the way. Muñoz, in both contexts, was a huge reason why.

If the eighth-inning matchup was a preview of what might come in October, everyone who tuned in is in for another treat.