A list of all players who have ever played Relief pitcher for the Houston Astros, with photos of the players when available. These Houston Astros Relief pitchers are listed by popularity, so the top of this list features only the best Houston Astros Relief pitchers of all time. The Houston Astros have a rich history with the MLB, and they owe a lot of their success to their talented Relief pitchers. This list answers the question, "Who are the greatest Houston Astros Relief pitchers of all time?"This list has a variety of items, like Roger Clemens and Nolan Ryan, in it.