According to Greg Rajan and verified on the PCL transactions page, Oklahoma City pitcher Douglas Arguello was released today. Arguello, who was a Texas League All-Star as a starter in 2009 and 2010, struggled with control this season, allowing 46BB in 68.2 innings as he moved from starter to reliever. However, he was still having a decent season overall, buoyed by a .214 opponents BA and a nearly 2:1 ground ball to fly ball ratio.
Arguello had arguably improved year after year since being stretched out as a starter at Tri-City in 2005, but perhaps after almost 10 years in the system the Astros simply didn't see him as a prospect any more. He's still just 26 years old, and given that he's a lefty I imagine he'll get picked up and given a shot elsewhere next season.