DENVER -- Colorado Rockies manager Jim Tracy resigned Sunday, stepping down after the team set a franchise record for losses.
The Rockies said a search for Tracy's replacement would begin immediately. Colorado finished last in the NL West this year while going 64-98.
Tracy was promoted from bench coach to manager in May 2009. He was voted the NL Manager of the Year that season after guiding Colorado into the playoffs.
The Rockies went 294-308 under Tracy.
"I was surprised," Bill Geivett, the team's director of major league operations, told The Associated Press. "I wanted Jim to come back. That's how we began our conversation on Friday, that he was the manager. But he called, informed me today he was resigning."
Tracy had said repeatedly over the past several weeks that he wanted to fulfill the final year on his contract in 2013, but he changed his mind after meeting with Geivett for several hours on Friday and then mulling those discussions over the weekend.
The Denver Post reported that Tracy felt uncomfortable with his role after changes were made to the front office Aug. 1.
Geivett said he had no timetable for hiring a new manager.
"Everything up to this point has been focused on bringing Jim Tracy back," he said.
Rockies outfielder Carlos Gonzalez also believed Tracy would return, the Denver Post reported.
"Jim Tracy's resignation is something I truly regret since he gave me the (chance) to play in the major leagues and prove my talent," Gonzalez told the Post. "It has always been an honor to play for him. I always believed he would have a chance to be with us next year.
"He is truly respected inside our clubhouse and I hoped he would be with us so he could help us improve and have a better season in 2013. Sadly, we had one of the worst seasons in franchise history and when these things happen our jobs are at stake."
Left-hander Jeff Francis said he was surprised to hear Tracy had decided to step down, telling The Associated Press in an email: "I loved playing for him and I think everyone did. The Rockies will miss him for sure."
Among the most vocal supporters was outfielder Dexter Fowler, who appreciated Tracy sticking with him through protracted slumps over the last two seasons before a breakout 2012. He tweeted, "Man I'm gonna miss Tracy, thanks for believing in me! You are a wonderful and stand up guy!"
Also leaving the coaching staff were hitting instructor Carney Lansford and third-base coach Rich Dauer, who were both dismissed Monday night, according to the Post.
The Rockies will be the fourth team to change managers this year. Boston fired Bobby Valentine, Cleveland dismissed Manny Acta and Houston let go of Brad Mills.
Geivett said it was a difficult day because his friendship with Tracy goes back two decades. They also worked together with the old Montreal Expos and with the Los Angeles Dodgers.
Things changed for Tracy on Aug. 1 when Geivett, the assistant general manager, was given an office in the clubhouse and began focusing on roster management, particularly as it related to the pitchers, and evaluating the coaching staff. Tracy's responsibilities were narrowed to game management and meeting with the media.
Geivett said that structure will remain in place next season, but he said he didn't think that would be an issue in his search for a new manager.
In addition to altering their front office, with general manager Dan O'Dowd refocusing his attention on the minor leagues and player development while Geivett focused on major league operations, the Rockies last summer adopted a radical four-man rotation and a 75-pitch limit for two months.
Geivett said the Rockies will return to a traditional five-man rotation next season with pitch limits determined on a case-by-case basis, "although I don't think we'll ever go back to the days of 120 pitches."
Tracy, the fifth manager in club history, was given an indefinite contract extension last spring but it guaranteed only his 2013 salary of $1.4 million as field manager and really just represented the organization's desire to keep him in the organization in some capacity.
Information from The Associated Press was used in this report.