The Theoretical Attack of a Bullpen-Focused Felix Hernandez

The slow progression that leads to a self-acknowledged decline was a process Felix Hernandez, unfortunately, entirely skipped. His career arch was a natural regression to average, injury, failure to adjust; sudden, poignant, and ridden of organizational, cognitive bias. The stark drop-off resulted in a split between a player who once meant everything being the roughest point in a rotation embattled in a playoff race. The hope that Hernandez could return to a balanced tactician on the mound was probably maintained one game too long – the last time he held a team to no runs was on opening day. Even more egregious, there was no subtle change to change his approach. The long leash of hope allowed him to stay stagnantly desperate.

His last outing against the Texas Rangers was the final capitulation to put him into the bullpen, no longer scheduled to make his start on Sunday August 12. The seven runs he allowed were built off his consist frustration leading to a parochial process. He no longer worked through counts with cognition for how batters were attacking – he was simply throwing. Analytically, Hernandez works from a fastball to a breaking ball; speed leading to mistimed swinging later in the count. Simply put, his fastball is necessary for leading into the breaking ball, and with his fastball dead in the water, his breaking ball is also dead. Batters no longer deceived now look forward to teeing off on a very predictable and forced breaking ball.

As the arm dies, the fastball dies. The changeup and breaking ball, however, does not always die. Furthermore, spin may die on the curveball, but spin rate makes an average curve deadly. Henceforth, Hernandez, does not need an incredible fastball to work toward an average changeup/curve. Yet, as a starter he has failed to figure out how to work into his changeup; he is beholden to a fastball which no longer averages 90 MPH. Experimenting with velocity and pitch utilization reached a maxim in 2018, leading to nowhere even after dropping the four-seam fastball. It is a crutch he has been unable to move past.

The following charts display how Hernandez has attacked batters based on the count from 2012, 2016, and 2018. As stated, in 2012, he used his fastball to work into a changeup on ahead counts ahead or a sinker when behind. Through 2016 and 2018, injury forced him to drop the fastball on the opening pitch, instead of using the fastball sinker. This creates two problems: the sinker is no longer effective to land a strike when behind counts because it is used as the opening pitch and the sinker becomes exposed to each batter, leading to the predictable approach. His sinker now owns a 1.64 BB/K ratio with a 1.001 OPS.

Moving to the bullpen should not necessarily be a point to fix Hernandez for an eventual transition as a starter. He is, for better or worse, an abbreviated pitcher, and as of right now, cannot endure multiple innings. His limited arsenal establishes him as a stretch reliever for two innings at best. To become an endurance starter, he needs to improve his curveball to break across both sides of the plate – or, McCullerize himself.

The focus for 2018 Hernandez is bullpen effectiveness and no more. Unfortunately, precedent for a pitcher in the Statcast era who utilizes a slow fastball and curveball/changeup is limited; limited to Sean Marshall. (This is assuming that Hernandez continues to forego his fastball in the bullpen. Most curveball relievers have a fastball which averages 93-97 MPH. Fernando Rodney is another reliever who is comparable with a sinker/changeup arsenal, but even he has maintained a 94 MPH sinker at age 41.) Thus, there is some new paths to be paved with Hernandez in the bullpen, making the transition even more intriguing.

The main goal in the bullpen is inducing ground balls; that was the magic of Hernandez’s changeup in his prime. Marshall achieved this in his prime with ground ball rates of 52.2, 57.5, and 56.3 percent from 2010 to 2012. He opened his counts with a slider, moving to a curveball when ahead and staying with his slider when behind. His curveball broke left (right from Marshall’s view) and was best when slyly placed out of the zone.

Hernandez breaks his curveball in the same style, just the opposite direction. In fact, while the spin rate has dropped, without injury, there is a clear improvement in control (2018 curve map versus 2015 curve map). Using the curve to introduce batters can theoretically be complemented by a changeup which paints the other side of the plate. Even so, his changeup is falling more in the zone as he ages (implicative of lack of a fastball to paint the inside, 2012 changeup versus 2018 changeup).

Putting the different strings together, a bullpen focused Hernandez would utilize a curveball to specialize for attacking the right side of the plate, with an increase to break across both aspects. His changeup then becomes the quick out option to force quick ground balls. If he slowly beings to move that pitch into the corner of the zone again, he can end at-bats on weak contact and topped contact. Despite his demise, the changeup is a quality pitch for inducing topped contact if he is ahead of counts. (Emphasis on if, and, there is a base loss of control which cannot be ignored; again, the point he is a limited inning pitcher with an onus on control). Thus, control with the curve to land a strike or foul from the corner can lead to an inning of what might remain of a magical changeup.

We hoped you liked reading The Theoretical Attack of a Bullpen-Focused Felix Hernandez by Alexander Haynes!

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I don’t believe he will be effective. Velo is important for relievers unless they are specialty pitchers. Even if he gets a 2 mph boost it is still only 92-93.

The starters turned relievers who dominate are all hard throwers with a good secondary who lack a third pitch and command.


I had thought similar on the walking corpse of Yovanni Gallardo.