The Mariners breakout that could create a surprising problem in 2025

As soon as the Seattle Mariners shut down George Kirby with inflammation in his throwing shoulder, there was a clear favorite to fill in for him in the rotation. Yet if there wasn't then, there's an interesting hypothetical hanging in the air right now.

What if Emerson Hancock proves to be better than a mere placeholder?

That he's going to get his shot as Seattle's No. 5 starter is no longer theoretical. As Adam Jude of the Seattle Times reported Wednesday, the 25-year-old righty has earned it, not to mention a proper blessing from manager Dan Wilson.

“He’s really had a good camp. I think he’s really taken a step forward here,” Wilson said, per Jude. “He has attacked the zone and really has gotten comfortable with the stuff that he has and how he’s going to use it, and it’s really made the difference for him.”

Hancock seems ready to turn a corner

Simply by virtue of having been the team's No. 6 pick in the 2020 draft, Hancock has been A Guy in the Mariners organization for a while. He just hasn't been A Guy in the chances he's gotten in the majors, producing a 4.71 ERA in 15 starts.

The 4.61 ERA he has in five starts this spring is eerily similar to that figure, and it hasn't been hard for hitters to reach base against him. In 13.2 innings, he's allowed 19 hits. It is small sample size season, however, and Hancock has rallied his last two times out in the Cactus League. He's pitched eight innings and allowed one run.

You can tell Hancock is a Mariners pitcher by how well he controls the strike zone, as he's allowed only three walks this spring and 22 in 72.2 innings in the regular season. Yet the real revelation this spring has been his stuff. In a word, it looks elevated.

After averaging 93.3 mph last season, he's at 94.5 mph with his four-seamer and sinker this spring. He's also showcased a new sweeper that averages 14.2 inches of glove-side movement, equivalent to the league average for right-handed sweepers in 2024.

That new pitch could pair well with Hancock's changeup, which is already known for its uncommon arm-side break.

The Mariners aren't hoping for Hancock to become an ace in Kirby's stead. Per Jude's report, Wilson only envisions him as a guy who's "gonna get ground balls" and "keep the game moving."

How the Mariners could handle a sudden starting pitching surplus

Kirby doesn't expect to be sidelined for much longer after the Mariners begin their regular season on March 27. He wants to be back by the middle of April.

Once Kirby is ready to return, the Mariners could face a simple decision with Hancock. If his warm spring doesn't beget a hot start to the regular season, they could either move him to the bullpen or send him back down to Triple-A Tacoma. He has two minor league options left.

But what if Hancock breaks all the way out, thus realizing the potential that made him a high draft pick just five years ago? In that event, three feasible options would have to be on the table:

1. Send him down anyway.
2. Go to a six-man rotation.
3. Make a trade.

Option No. 1 would be a downer, and not just for Hancock but for Mariners fans as well. Nobody is rooting for him to fail, much less be banished to the minors no matter how he's pitching in the majors.

Hence why Option No. 2 would have the be a consideration for the Mariners. And if there's a benefit to that approach, it involves potentially circumventing burnout. The team got a league-leading 942.2 innings from its starters in 2024, but the Kirby injury should have them questioning how much further they can push their luck in demanding high such workloads from their starters.

On the other hand, more guys in the rotation fundamentally means fewer starts by Logan Gilbert, Luis Castillo, Bryce Miller and Bryan Woo, not to mention for Kirby and Hancock in their own right. That would only be worth it if the extra rest kept everyone healthy. Even then, the Mariners would have to wonder if their top starters would have survived a standard five-man rotation anyway.

Which brings us to Option No. 3.

As much as Mariners president of baseball operations Jerry Dipoto likes to talk a good game about subtracting from the team's wealth of arms as "Plan Zero," he clearly considered it during the winter. Trade rumors were swirling around Castillo, and it doesn't take an especially keen pair of eyes to spot teams that could get in on him if he was to land back on the trading block.

Sans Gerrit Cole, the New York Yankees are clearly one. The New York Mets similarly have major injury issues in their rotation. The Baltimore Orioles never did find a replacement for Corbin Burnes, and now Grayson Rodriguez is hurt again.

Then again, it's easy to play fantasy baseball with respect to hypothetical trades. Dipoto's position is more complicated, as he should know from the Kendall Graveman and Paul Sewald trades that in-season deals of core players aren't the best for clubhouse morale.

Which is ultimately to say that the Mariners won't have a "right" decision to make in the event that they find themselves with six viable pitchers instead of five. What choices they'll have will instead be varying degrees of unpopular.

Then again, this would also be one of those nice problems to have. Certainly nicer, of course, than watching Hancock continue to struggle and having to banish him to the minors in a more unceremonious fashion.