Washington claimed Armenteros off waivers from the Diamondbacks last December, but he never appeared in a big league game with the Nats. He began the season with Triple-A Rochester, and was outrighted off the 40-man roster after being designated for assignment in June. Armenteros landed on the minor league injured list not long after, and he made one rehab appearance with the Nats’ complex league affiliate last weekend before being released.
While Armenteros’ tenure with the Nationals didn’t go as hoped, he’s not far removed from a generally well-regarded arm. Baseball America slotted Armenteros among the top thirty prospects in the Astros’ system in each season from 2017-20, thanks to his plus changeup and strike-throwing acumen. Armenteros has a 1.94 ERA over 83 2/3 innings at the Double-A level and has a decent 4.04 mark in 300 2/3 career innings at Triple-A. His big league experience consists of 18 innings with Houston in 2019, as he pitched to an even 4.00 ERA with solid strikeout (24%) and walk (6.7%) rates.