A February 2021 signee out of the Dominican Republic when he was 18 years old, Mendez moved to full-season ball for good in 2023 but found it difficult to move beyond Single-A Lake Elsinore until this spring. Facing Rule 5 eligibility this offseason, the 6-foot-2 right-hander has exploded on the scene with killer stuff and improved control, aiding the belief that he could be a starter and solidifying his place as one of the most electric arms in the San Diego system.
Mendez has ramped up his four-seam fastball to touch 100 mph at times this season, and even when he sits more in the 95-98 mph range, there is still explosive life up in the zone that he’s used to blow past low-level bats. His mid-80s slider plays off that well, breaking late and just in time to fool hitters who were sitting on the heater. Lefties have just as much of a problem with the breaking ball as righties with half-hearted swings once they realize they’ve been fooled. That’s needed because while Mendez has an upper-80s changeup, it’s too firm to do more than simply change speeds.
Mendez went from walking 14.9 percent of his batters faced to getting that number into single digits this summer, a very promising trendline for such a hard thrower. The lack of a true third pitch brings along its own relief risk, but with the quality of his two best offerings, he’d be a safe bet to thrive in a shorter role too. Having turned 23 in July, Mendez could be a Major League option in any capacity by next season if the stuff and control continue to hold.