Castillo, who suffered a season-ending torn labrum in his right shoulder in June, had been on the 60-day disabled list since July 3. As the Reds are working to finalize their 40-man roster in advance of the Dec. 10 Rule 5 Draft, Castillo was reinstated from the DL on Monday and then outrighted off the roster. The Reds and Castillo immediately agreed to terms on a Minor League contract, which ensures that Castillo will participate in Spring Training with Cincinnati.
Though he did spend some time on the Major League roster, Castillo only had three at-bats with the Reds in '09. The majority of his appearances last season came in Triple-A Louisville, where he hit .221 in 37 games.
Unlike Castillo, outfielder Darnell McDonald has chosen to look elsewhere for playing time in 2010. The Reds announced on Monday that McDonald, who was outrighted off the 40-man roster on Thursday, has elected to become a free agent.
McDonald appeared in 47 games for the Reds last year, batting .267 with 10 RBIs and 12 runs scored.
The Reds have also lost right-hander Ramon Ramirez, who has been claimed off waivers by the Rays. Ramirez made 11 appearances out of the bullpen for manager Dusty Baker in '09, finishing with a 3.65 ERA in 12 1/3 innings. Ramirez went 6-7 with a 4.03 ERA in 31 games (20 starts) for Louisville.
Jenifer Langosch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.