Analysis: How Should Mariners Handle George Kirby, Logan Gilbert Down Stretch?

Logan Gilbert and George Kirby have had tremendous success to start their respective careers in Seattle. They are two of the best young starters MLB has to offer, but they currently find themselves in uncharted waters, seeing career highs in pitches thrown.

For a Mariners team trying for their first playoff berth in 20 years, what is the right balance between caution and winning?

Seattle has markers it looks for in each pitcher, including signs of fatigue, velocity declines and word from the pitcher themselves that they are feeling rundown. For example: Gilbert's velocity could stay up, but the team has other metrics and film that may indicate he is starting to tire. 

There's also the topic of an "innings limit." This term can be vague, because there are so many factors to consider here. A pitcher like Kirby may be nearing his innings limit, but because he has been so effective in keeping his pitch count down, his arm and body are taking on a reduced amount of stress on a per outing basis.

Over 100 pitches in six innings is much more stressful than 75 in the same amount of time, so not all innings are created equal. The Mariners will obviously have the best interest of both players in mind, even if they are moving closer and closer to snapping a playoff drought. 

Seattle has many options at its disposal to combat a slowdown for Kirby and Gilbert. 

The goal should ultimately be to keep the two pitching and fresh to pitch in the playoffs. It wouldn't make sense to waste their bullets during the regular season, when one or both could pitch in October.

As the playoffs fast approach, the Mariners could invoke a "soft cap" on thier young pitchers, essentially reducing the action they see game-to-game in September. Seattle now has three intriguing bullpen options that can pick up any vacated innings: Matthew Boyd, Chris Flexen and Matt Brash.

Skipping a start is another option. Seattle could easily skip Kirby or Gilbert, replacing him with Flexen and giving some extended time off. Flexen still gives the club a good chance to win, and if it plans it around an off day it could skip both on the same turn through the rotation.

Seattle likely will begin to employ these strategies to save these two arms, who will be crucial to winning games in October.