PEORIA, Ariz. — The Seattle Mariners are entering their second season under hitting coach Kevin Seitzer, and if early signs from spring training are any indication, the offensive ceiling in Seattle may be higher than critics expect. After finishing 10th in Major League Baseball last season with a .740 OPS — an impressive feat considering half their games are played at pitcher-friendly T-Mobile Park — the Mariners are not talking about maintaining progress. They are talking about accelerating it.

Seitzer, a two-time All-Star during his playing days and a former American League hits leader, joined Seattle Sports’ “Brock and Salk” live from camp on Friday and did not hesitate when asked which bats are jumping out early. His answers were revealing, confident, and perhaps most importantly, pointed directly at the players who could redefine Seattle’s offensive narrative in 2026.

First on that list? Julio Rodríguez.

The Mariners’ superstar center fielder is entering his fifth MLB season with expectations no longer merely high but enormous. Rodríguez’s 2025 campaign was a tale of two halves. Through late May, he struggled to find rhythm, batting just .227 with a .714 OPS — a frustrating continuation of his career-long pattern of slow starts. But from that point forward, something shifted. Over his final 110 games, Rodríguez slashed .285/.333/.503 with an .836 OPS and 23 home runs, reestablishing himself as one of baseball’s most electric talents.

Seitzer believes the early-season inconsistency may finally be over.

“All of our guys went through ups and downs,” Seitzer said in Peoria. “Julio getting off to his prototypical slow start — I think, I hope — I think that’s going to end this year. I think he’s going to be more consistent.”

That word — consistent — may be the most important one uttered this spring.

Rodríguez famously opted not to participate in last year’s MLB All-Star Game despite making the American League roster, a decision that raised eyebrows at the time. Almost immediately afterward, his offensive production surged. According to Seitzer, the period surrounding the All-Star break became a pivotal learning moment.

“I felt like there was a turning point,” he said. “There was a lot that we learned, and he learned. My hope is that’s going to be the big wow.”

If Rodríguez carries that second-half momentum into April rather than June, the American League West could look dramatically different.

But Seitzer’s optimism does not stop with established stars.

When asked which players have stood out most in camp, he pointed to two of the organization’s brightest young prospects: Colt Emerson and Michael Arroyo.

Emerson, a 20-year-old shortstop who has also been seeing time at third base, ranks as the No. 9 overall prospect in baseball according to MLB Pipeline. Arroyo, a 21-year-old infielder expected to log time in the outfield, sits at No. 67 on the same list. Rankings, however, are only part of the story.

“Colt Emerson looks really good right now. I’m a big fan. It’s impressive,” Seitzer said. “Michael Arroyo looks really good right now.”

Then came perhaps the most telling observation.

“Both of them got slow heartbeats in that batter’s box, and that’s pretty special.”

In baseball language, a “slow heartbeat” signals composure beyond years — the ability to control at-bats rather than react to them. It is the difference between surviving and dictating. Seitzer noted their pitch recognition, their disciplined takes, and the controlled nature of their swings, particularly impressive given how early it remains in the spring calendar.

“These guys ain’t supposed to have timing right now,” he added. “Those two guys have been the ones that have really jumped out at me.”

For a franchise that has built its identity around elite pitching and athletic defense, sustained offensive growth has been the missing accelerator. Last year’s top-10 OPS finish suggested meaningful progress, especially within the challenging dimensions of T-Mobile Park. The collaboration between Seitzer and senior director of hitting strategy Edgar Martínez — a Hall of Famer with two batting titles — has clearly injected structure and accountability into the lineup’s approach.

Now, the Mariners appear positioned at a crossroads between potential and payoff.

Rodríguez refining consistency. Emerson and Arroyo pushing from within. Veterans absorbing a unified hitting philosophy. It is a convergence that could redefine Seattle’s ceiling in 2026.

Spring training optimism is hardly rare, but Seitzer’s tone felt less promotional and more analytical. He was not predicting breakout seasons. He was identifying adjustments, learning curves, and maturity signals that typically precede them.

If Rodríguez truly eliminates his early-season lulls, he enters legitimate MVP territory. If Emerson and Arroyo translate poise into production faster than expected, roster decisions will grow complicated in the best possible way.

The Mariners have spent recent years assembling a foundation. Now, according to their hitting coach, the next layer may be forming.

Seattle’s offense was good last season. It may be dangerous this one.

And if Kevin Seitzer’s evaluations prove accurate, the rest of baseball might soon be watching the Pacific Northwest with far greater urgency than before.