Unexpected Mariners headache destined to cost Seattle a World Series

This isn't how M's president of baseball operations Jerry Dipoto drew it up.
Seattle Mariners Draft Day
Seattle Mariners Draft Day | Alika Jenner/GettyImages

Seattle Mariners president of baseball operations Jerry Dipoto landing All-Star slugger Eugenio Suárez at this year's trade deadline was supposed to be a needle-mover. That's been the case, just not in the way he or the team had hoped. Granted, the club has been the second-hottest in baseball, trailing only the MLB-best Milwaukee Brewers freight train since its blockbuster swap.

But the Mariners, along with everybody else, expected Suárez to be the addition that bolstered their World Series chances. He was widely viewed as the missing piece in their heart of the order, on pace for 50+ homers amid a career year. However, at least thus far, the early signs of his arrival suggest the 34-year-old could do more harm than good come playoff time.

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Eugenio Suárez trade may come back to haunt the Mariners in October

Suárez's return to the Emerald City hasn't been as glamorous or fruitful as the Mariners hoped. Perhaps he's losing steam following a rampant first half of the 2025 campaign, considering the slump dates back to the end of his Arizona Diamondbacks tenure. Nonetheless, it's been a slog after seeing him mash 31 home runs and 78 RBI with a .250/.320/.569 slash line with a sterling .889 OPS before the trade deadline.

Entering Seattle's series finale against the Baltimore Orioles, Suárez is batting .114/.167/.205 with just one homer and five RBI across 44 at-bats with his new (old) team. Strikeouts have always been part of Suárez's game, though his K rate has been alarmingly high with the Mariners (35.4 percent, well above league average). The sample size is incredibly small, of course, and this can age poorly at any moment. But what's changed so changed so drastically that has led to such a sharp decline?

Why has Eugenio Suárez struggled early in Mariners reunion?

Going from one of the most hitter-friendly stadiums in Arizona to the most daunting environment for a batter in the Majors is a logical explanation. Yet, as mentioned, Suárez's struggles began with the Diamondbacks. Nor is this his first stint with the M's; we saw him mash in the Mariners' T-Mobile Park in 2022 and 2023.

Notably, Suárez posted better or near-identical home/road splits in each of his two previous seasons with the Mariners. Now, surrounded by more firepower amid arguably a career year, he's not faring well regardless of location. Maybe this is just a poorly timed cold spell rather than anything wrong under the hood. Either way, though, Seattle can't afford it to last too much longer.