Astros pitcher Wandy Rodriguez is headed to the 15-day disabled list due to fluid buildup in his elbow. It's bad news for Houston, who has seen staff "ace" Brett Myers slide in the past month while Wandy has been coming on strong as of late.

One potential bright spot is that the Astros are calling up their one and only bona fide prospect, Jordan Lyles, from AAA Oklahoma City. Lyles, 20, is expected to pitch in Chicago Tuesday against the Cubs. Lyles is 3-3 with a 3.20 ERA for the Redhawks this season, with a WHIP (walks plus hits per innings pitched) of 1.24.

Rodriguez  has been solid for Houston in 2011 after a rocky start. He has pitched at least seven innings in seven of his ten starts, while amassing a 3-3 record. Wandy hasn't given up more than three earned runs in a start since April 24, and was 2-0 with a 2.25 ERA in May.

Lyles was already a virtual lock to hit the Bigs for September call-ups, so he's going to start collecting a Major League check a few months earlier than planned.