HOUSTON --The Houston Astros have relieved pitching coach Brad Arnsberg of his duties. Astros' General Manager Ed Wade said the decision was made as a result of philosophical differences. However, the results on the field haven't been great this season -- the staff is ranked second to last in the National League in team ERA (4.69), last in the NL in batting average against (.269) and first in the NL in earned runs against (306). Former Astros pitcher Doug Brocail, who had been serving as a Special Assistant to the General Manager, will replace Arnsberg on an interim basis. Brocail, 44, pitched for 15 seasons in the Major Leagues, including four with the Astros. Since retiring after the 2009 season, Brocail has assisted with the evaluation of Major League and minor league players in the Astros system and has handled some Major League scouting assignments. Arnsberg had served as the Astros pitching coach since being hired on October 30, 2009. The Astros currently have the worst record in baseball at 25-42.