Mariners finalizing four-year extension with reliever Andres Munoz

The Mariners are finalizing agreement on a four-year extension with reliever Andrés Muñoz that guarantees at least $7.5M, reports Daniel Kramer and Jesse Sanchez of MLB.com (Twitter link). The deal contains three club options, reports Jon Morosi of MLB.com (on Twitter).

Muñoz, a client of Hector Gomez, had been controllable via arbitration through 2025. The deal buys out his final pre-arb season in 2022, as well as all three arb years. The Mariners extend their window of control by three seasons via the club options.

It’s a fascinating agreement, as Muñoz has made exactly one appearance in a Seattle uniform. He recorded two outs during the M’s season finale against the Angels, his first big-league work since his time with the Padres in 2019. Those two seasons mark the entirety of Muñoz’s big-league career, as he has just 23 2/3 innings of 3.80 ERA ball under his belt at the highest level.

That limited track record is on account of both youth and injury. The Mexico native is still just 22 years old (23 in January), having reached the big leagues at age-20. He blew out his elbow in spring training with San Diego in 2020, requiring a Tommy John procedure. While he was rehabbing, Seattle acquired him as part of the seven-player Austin Nola deal. He spent the next year recovering under the eyes of Mariners’ medical personnel before returning to health in time for the season’s final game.

That lack of track record makes Muñoz a rather atypical extension candidate, but it’s also easy to understand why the Seattle front office jumped at the opportunity to lock in some eminently affordable rates over the coming seasons. Muñoz possesses electric stuff, including one of the game’s hardest fastballs. He averaged triple digits on the pitch during his 2019 rookie campaign. Upon his return from injury, that average heater had “dipped” to 99.6 MPH. Were Muñoz to emerge as a potential closer or even simply a high-leverage relief arm, he’d stand to earn far greater than a cumulative $7.5M through arbitration. And that’s before considering the most appealing part of the deal from a team perspective — the opportunity to extend their window of control an additional three seasons.

From Muñoz’s perspective, the deal affords him the opportunity for up-front financial security. It’s possible he’ll wind up underpaid, if he lives up to his immense upside. Yet it’s difficult to fault a player his age for locking in this kind of money, particularly given that he’s yet to establish himself within a big-league bullpen. Even independent of injury concerns, Muñoz comes with questions about his strike-throwing ability. He routinely walked upwards of 11% of opponents in the minors until 2019, and there’s a chance he never develops adequate command to match his power arsenal.

While the team can shoulder that kind of risk with relatively minor cost, Muñoz struggling early in his career could have had a significant impact on his earnings. He’ll forfeit a fair bit of ceiling in order to avoid that downside. All told, it’s a fascinating gambit for Seattle — one that, while unconventional, has the opportunity to pay off handsomely if Muñoz emerges as a late-game weapon.