Why Red Sox fans should be concerned with Ranger Suarez's fastball

Ranger Suarez certainly does not light up the radar gun. 

The new addition to the starting rotation of the Boston Red Sox averaged 90.5 mph on his fastball with the Philadelphia Phillies in 2025, placing the lefty in the seventh percentile among MLB pitchers. 

Every hitter knows Suarez likes to work the corners and induce weak contact, but how long can he be effective before age and the lack of velocity catch up to him? 

"The concern is how long he can keep it going. Last season, 127 pitchers threw at least 100 innings. Twenty of them, including Suarez, featured fastballs that averaged less than 92 mph. That group combined for a 4.34 ERA. Not awful, but it points to how Suarez has been an outlier among this type of pitcher," ESPN's David Schoenfield wrote. 

"That alone doesn't mean he can't keep it going for the next four or five years if he stays healthy, but if he loses even a little off his fastball, it could be a big issue." 

How Suarez can remain effective 

Suarez doesn't strikeout a ton of batters. But the Red Sox won't need him to rack up the punchouts if he continues what made him an All-Star in Philadelphia. 

"Suarez's history of minor injuries over the past four seasons -- combined with a fastball that averages just 91 mph -- makes his future an interesting bet," added Schoenfield. "He compensates for his lack of velocity with a wide arsenal of pitches, especially his outstanding curveball and changeup, which helps his sinker and four-seamer play up. He also uses a cutter against right-handed batters and a slider against lefties." 

His wide-ranging pitch mix and command led to a 5.8% walk rate and 3.20 ERA in 26 starts with the Phillies last season. 

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