The Nationals lost hard-throwing reliever Cole Kimball today when the Toronto Blue Jays claimed him off of waivers. Kimball, 26, made his major league debut this year for the Nationals and looked like one of their most promising relief pitchers until he tore the labrum in his right shoulder. Kimball will be able to pitch again in the majors by the all-star break at the earliest.

(Christian Petersen/GETTY IMAGES)

Kimball’s stock within the organization skyrocketed during his 2010 minor league season and Arizona Fall League appearance, when he converted to the bullpen and his fastball-splitter combination made him a late-inning relief candidate. His performance this spring training, when his fastball hit the upper 90s, added to the buzz around Kimball. His intensity ranged between comedic and borderline scary.

Kimball began to feel soreness in his throwing shoulder shortly after spring training, a pain exacerbated by the cold at Class AAA Syracuse. But he told no team medical personnel and still pitched well, and the Nationals summoned him to the majors in May. He made 12 appearances, posting a 1.93 ERA in 14 innings.

On June 9, Kimball pitched 2/3 of an inning in San Diego and had to leave the game. His shoulder had become untenable, and after he tried to rehab, further tests revealed he needed the labrum surgery, one of the most difficult injuries for a pitcher, especially one with a violent delivery like Kimball, to recover from.

The Nationals also outrighted outfielder Corey Brown to Class AAA Syracuse, which clears a 40-man roster spot. Brown, who came to the Nationals from Oakland along with reliever Henry Rodriguez in a trade for Josh Willingham, had been a September call-up. The Nationals currently have 32 players on their roster.