"Any time you lose as many games as we lost, you've got to take a look at every part of the operation and see where we think we can improve," Luhnow said. "I think everybody on the staff did a good job this year. Whether or not they had the resources they needed to be successful is one thing we could discuss, but when Bo and I talked about it we felt a couple of new voices would give us a chance to mix things up a bit and potentially help us improve on the field."
Luhnow said bench coach Eduardo Perez and third-base coach Dave Trembley have been offered contracts to return next season, though he didn't specify in what capacity. Hitting coach John Mallee is coming back for 2014.
The GM said he and his staff would begin putting a list together Wednesday for possible candidates to take over as pitching coach.
The Astros plan to hire a pitching coach who will have input in the bullpen coach hire because both positions have to be on the same page. Additionally, Luhnow said he would like to add a coach with a background working with middle infielders to help along the development of shortstop Jonathan Villar and second baseman Jose Altuve.
"That's the one technical area we were missing this year, someone that has middle-infield experience," he said.
The move of Brocail into a new role was done in conjunction between Luhnow and Brocail, who had served as pitching coach since June 14, 2011. Prior to that, Brocail worked nearly two years (2010-11) as a special assistant to the GM after a 15-year career that included two stops in Houston.
Brocail will help with pitchers throughout the organization, which has bolstered its pitching depth considerably in the last few years by adding arms like Mark Appel, Brady Rodgers, Kent Emanuel, Andrew Thurman and Lance McCullers Jr. to join up-and-comers like Mike Foltynewicz, Asher Wojciechowski and Vincent Velasquez.
The Astros ranked last in the Majors in ERA this season, but they had the youngest staff in the league. What's more, several young pitchers showed promise, led by starters Jarred Cosart, Brett Oberholtzer, Brad Peacock and Dallas Keuchel.
"Given the investments the organization was making in pitching, some of whom have been to the big leagues and a lot of whom haven't, Doug has a good feel for the organizational pitching philosophy and it's a great opportunity to get him involved like he was before he took this [pitching coach] role," Luhnow said.
Martinez, 58, was with the Astros for only one season after working as a pitching coach in the Cardinals organization for six years. Luhnow admitted Brocail and Martinez didn't see eye-to-eye early in the season.
"There might have been a few miscommunications," he said. "That's to be expected when you're putting two people together who have never worked before, which is why when we're talking about hiring a new pitching coach, we felt it important to give that person the opportunity to be involved in the recruiting and selection of a bullpen coach. They need to be joined at the hip."
Martinez said he was disappointed in the decision and felt he worked fine with Brocail.
"I don't know what the situation was to be let go, but they decided to let me go and they said they want to bring in a pitching coach and a guy he can get used to and be on the same page with him," he said. "I don't know what that means. I thought Brocail and I were on the same page, but I guess I was wrong. I didn't feel that way. I don't think that was true. I'll just take it as a professional and move on."
Clark, 51, spent five consecutive seasons on the Astros coaching staff, serving as the third-base coach for four seasons (2009-12) and the first-base coach this season. He had been with the organization since 2005, managing at Double-A Corpus Christi for three years and Triple-A Round Rock for one year.
Clark also served as interim manager at the end of the 2009 season when Cecil Cooper was let go, managing the final 13 games.
"The Astros thank Dave Clark for his many years of service to the organization and wish him the best going forward," Luhnow said.
Clark was in charge of the baserunning, and Porter told reporters in September he was planning to take over baserunning coaching after the Astros made several mistakes on the bases. Clark and Brocail were the only coaches Porter inherited.