Signed by the Nationals for $35,000 out of Panama in 2013, Fuentes pitched to mixed results in multiple roles early in his career but began to put it all together in 2018. He built upon that success during a breakout age-22 campaign in 2019, excelling as a reliever at Class A Advanced Potomac and then as a starter at Double-A Harrisburg. But after compiling a 2.23 ERA with 89 strikeouts and 22 walks in 80 2/3 innings between the two stops, Fuentes was slapped with a 50-game suspension in early August after testing positive for Heptaminol, a banned stimulant.
Fuentes succeeds with an intriguing blend of stuff and pitchability. His fastball can touch 95 mph and sits in the low 90s with heavy sinking action that fuels the right-hander’s extreme ground-ball tendencies. He posted a 58 percent ground-ball rate in Double-A before the suspension and has induced grounders at 54.2 percent clip since the start of the 2017 season, his first in full-season ball. Both his average slider and his above-average changeup improved when he moved into the rotation, and he generated whiff rates of 41 and 40 percent, respectively, with the two pitches in the Eastern League. He can throw all three pitches for strikes and doesn't hurt himself by issuing many free passes.
Fuentes' ability to work effectively in various roles is an asset, and club officials view him as a potential multi-inning reliever much like former Nats hurler Yusmeiro Petit. At the same time, it wouldn't surprise anyone in the organization if Fuentes were to continue to excel as a starter en route to a spot in the back of a big league rotation.