Ranger Suárez has been nothing short of a major boost to the Philadelphia Phillies this season. The left-hander pitched out of the bullpen to start and eventually found himself in the closer’s role, posting a 1.12 ERA across 27 relief appearances with four saves in seven opportunities. However, injuries and ineffectiveness in the Phillies rotation led them to converting Suárez back into a starter, a role he had not occupied in the Majors since 2018.

So far, Suárez’ 2021 success has translated from the bullpen to the rotation. In 6 starts, Suárez has a 2.03 ERA with 1.31 WHIP. The increased velocity he displayed as a reliever has traveled with him into the rotation. Last time he was a starter in 2018, he was averaging 92 MPH on his fastball and 90 on his sinker. Now, those numbers are up to 94 and 93 respectively. That has allowed his strikeout percentage to jump from 16% in 2018 to 24% in 2021. That’s even an increase from his last season of significant playing time in 2019, when it was 20% in 37 big league appearances.

So the question remains: Can Ranger Suárez remain a starter long term?

How he has found success

Suárez succeeded in the bullpen with essentially a two-pitch mix. He attacked with his fastball/sinker and then put hitters away with his changeup. Suárez’ changeup has been very effective this season, with opponents hitting just .197 off of the pitch. 


His changeup effectiveness was on full display against the Rays on August 24th. Suárez threw his changeup a total of 30 times and generated seven whiffs. He generated nine total whiffs in his 6 ⅔ innings where he struck out seven and surrendered one run on six hits. Suárez relied heavily on his two-pitch combo in this game, throwing his slider just three times. The Phillies ultimately lost the game, but Suárez was extremely effective and left with the score at 1-1. 

via Baseball Savant

What he needs to do to continue that success

However, you need more than a two-pitch mix to be a starter. As a reliever, a pitcher can get away with two pitches because he is most likely seeing a hitter just once per game. But as a starter, a pitcher is seeing opposing hitters at least three times a game on average. You need an effective third pitch to help keep hitters guessing.

For Suárez, that third pitch is his slider. He has rarely used his slider this season in any capacity, as it makes up just under 6% of his usage rate. For comparison’s sake, Suárez throws his changeup 24% of the time with the fastball/sinker making up the rest. Suárez’ latest start against the Diamondbacks is a near perfect blueprint for what he needs to do to continue as an effective starter.

In that start, Suárez threw his slider 13 times, ten more than the previous start against Tampa. He generated four whiffs on the pitch, the most out of his pitches. However, this time his 12 total whiffs were more spread out among his pitches. He didn’t last as long in the game, going just 5 ⅓ but had the same amount of success, finishing with one run allowed on five hits with five K’s and collecting his first win as a starter since July 26th, 2018.

How can it be done?

Suárez has to continue to increase his slider usage in order to get a better feel for the pitch and develop it into a more effective weapon. That may be a challenge best suited for this offseason, but nevertheless, his start against Arizona is a step in the right direction in proving that the success he found in the bullpen can transfer over to the rotation with a heavier workload.