The Astros announced Tuesday afternoon that Castro was being placed on the 15-day disabled list due to discomfort in his right knee and would not appear in a game for the remainder of the season. He had played in only two games since aggravating his knee Sept. 2.
Castro had the cyst drained Sept. 3, one day after fouling a ball off the knee, and started consecutive games at designated hitter on Sept. 6-7 in Oakland, going 0-for-9. Castro later admitted he came back too soon, and he hasn't played since.
Castro missed the entire 2011 season after injuring his right knee in Spring Training of that year and having to undergo surgery to repair the anterior cruciate ligament. He played in 87 games last year, but was on the disabled list twice due to fluid in the knee.
This was a breakout season for Castro, a two-time American League Player of the Week and the first Astros player to represent the AL in an All-Star Game. He hit .276 in 120 games, with 35 doubles, 18 homers and 56 RBIs, as well as a .485 slugging percentage, setting career highs in every offensive category except triples.
Castro and backup Carlos Corporan were the only catchers on the roster for most of the season until a rash of injuries at the position. Corporan suffered a concussion on Aug. 19 and went on the disabled list. He was replaced by Minor League callup Max Stassi, who himself suffered a concussion two days later in only his second game in the Major Leagues.
The Astros were forced to call up 11-year Minor League veteran Cody Clark and trade for Matt Pagnozzi to provide some depth at catcher. Corporan returned to action only recently, and Stassi is expected to join the team Monday in Arlington following a rehab stint during instructional league this weekend in Kissimmee, Fla.
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.