Recently Signed Nationals Reliever Showing Positive Changes to His Pitch Repertoire

The Washington Nationals have desperately needed some bullpen help, and a recent veteran signing has found a way to be an integral part of the team.

May 6, 2025; Washington, District of Columbia, USA; Washington Nationals relief pitcher Andrew Chafin (53) delivers a pitch against the Cleveland Guardians during the sixth inning at Nationals Park. | James A. Pittman-Imagn Images

The Washington Nationals have been a somewhat hit or miss team in 2025, and many of the "miss" events have been due to the lack of bullpen success.

Closing out games has been an immense difficulty for the young team, and despite quite a few veteran arms to choose from, they have not found a level of consistency that has allowed them to win tight contests.

In recent weeks, they have decided to shuffle things up a bit, signing Andrew Chafin, designating Colin Poche for assignment and releasing Lucas Sims.

These moves have all been made with the hope of trying to solidify the room and give themselves a fighting chance at maintaining leads, especially with how well their starting pitchers have been performing.

The signing of Chafin was an intriguing one.

As a longtime veteran, he has shown some flashes of brilliance over the years, but has also struggled at times, as well.

The hope was he could be a player who brings some sort of juice to the bullpen for the next few months, and if possible, teach some of the younger arms in the room.

After a few weeks, it seems like he has something left in the tank.

In five appearances, he has a 2.25 ERA, 1.750 WHIP, five strikeouts to four walks and a 197 ERA+. While not perfect, he has been solid and has kept the runs to a minimum, which is all Washington can ask for right now.

Much of his success has come from a slight change to his repertoire.

What Changes Has Andrew Chafin Made?

The main alteration for Chafin -- not only this season but over the course of the past few -- has been dropping his four-seam fastball utilization.

According to Baseball Savant, in 2020, he was using his four-seam fastball 38% of the time, which, while not particularly high, is pretty substantial.

It then fell each of the next five years -- including this one -- until it has reached the point where he is using it 10.3% of the time in 2025.

This has happened due to the league-wide MLB usage also dropping in many cases.

As for Chafin, he has begun to favor his slider and sinker more often instead, throwing them 47.4% and 41% of the time, respectively.

This small change has allowed him to start off the year with some promising success, and while he may work the fastball in a bit more in the coming months as he continues to ramp up a bit, he clearly has begun to transition to a new choice of pitches that has served him well.