The Mariners are the new kings of pitching backwards

When reliever Austin Adams was dealt from the Washington Nationals to the Seattle Mariners back in May, he had something interesting to say about the use of his fastball, which was an important pitch to master:

“Just because fastball velocity has gone up doesn’t mean that fastball usage needs to go up as well. If anything it’s trending the opposite (way). With fastball velocity is going up, (for) a lot of teams fastball usage is going down. As a reliever, if I can have a hitter thinking 50–50 up there, then that’s the more pitches the better I can put in the back of their mind and they have to think about.”

While Adams’ results have been middle-of-the-road, his strikeout rate hasn’t been, whiffing 19 batters in just 13 ¹⁄₃ innings with the M’s.

Just recently, the spokespeople for the pitch-backwards revolution where probably the Yankees, who had the lowest fastball percentage in baseball in both 2017 and 2018. This season... it happens to be the Mariners.

Indeed, their propensity to pitch backwards has increased faster than even the league trend, especially over the last three years:

One example as the centerpiece of this revolution is Connor Sadzeck, a more respectable statistical bedfellow at a 2.66 ERA. Lookout Landing tracked his development first, stating:

“Sadzeck has been leading off at-bats with the slider, often getting called first strikes... [and] Not only is Sadzeck throwing his slider more, it also has a different quality of movement for the Mariners: about an inch more of vertical movement up in the zone, and less horizontal movement, per Brooks.”

Unsurprisingly, the Mariners are fifth in first-pitch-strike percentage, and that has stayed a consistent approach and strength over the last few years. Another example of the pitch-backwards approach actually revamping a starter is Marco Gonzales, the former top prospect flipped for Tyler O’Neill.

While Gonzales threw his fastball 57% of the time with the Cardinals before his Tommy John surgery, his arm will now continue to give him diminished velocity; as of now that’s 89 mph. Yet he’s thrown the four-seamer just 12.6% of the time in 2019, leaving the cutter to fill the void another quarter of the time. Another piece was boosting his spin rate, something Adams mentioned as a strategy. If there’s anything plaguing him with the 4.77 ERA this season, it’s a lessening of that:

That also brings us to King Felix Hernandez, who is in dire need of a revamping of his approach a la, let’s say, the right-handed version of CC Sabathia. Hernandez, to his credit, has essentially established himself as a sinker/curve pitcher, primarily:

Once again, the results have been illusive, as a lat issue and a 6.52 ERA would beg to differ that the results have been successful.

Yet with a rebuilding team, or any team in transition, the organizational elements of player development are arguably more important than results, for the sheer fact that having actual, talented ball players to implement these strategies are going to be more effective than retrofitting it to an aging Felix Hernandez.

Which is a long way of saying that the analytical footing that the Mariners are on is much stronger than in the Jack Z regime, or really another time since their last successful stretch of teams.

When you see a team implementing robust development strategies that are meant to make the best of players—hell, look at Dan Vogelbach on the position player side—it means you’re converting potential talent into current talent. When that ideology is adopted by a Justus Sheffield, or Jarred Kelenic, or George Kirby, that’s where you see these abstractions converted into wins.