Chris Walter, who worked as Gillett's assistant last year and spent 10 years as the team's Minor League strength and conditioning coordinator, will fill the job. He has already been on duty this offseason, working with Tigers players on workout plans.
"He has been up with the big league club at various times," team president/general manager Dave Dombrowski said at last week's Winter Meetings.
Gillett joined the Tigers as an intern in 2002 at Double-A Erie. He moved up to Toledo in '03, then spent '04 as the Tigers' Minor League strength and conditioning coordinator. Gillett replaced Dennie Taft in Detroit that fall and made an almost immediate impact in the system.
It was Gillett who worked with Detroit's many star players to help put together their offseason workout regimens, from the meticulous Justin Verlander to the intense Miguel Cabrera. Gillett traveled during the winter to visit players and witness their progress firsthand.
For several years, Gillett and Cabrera worked together to change his frame to go with his game. Gillett also helped Cabrera make the transition to third base in 2012 and regain some of his younger agility.
Gillett built a foundation for Tigers workout programs that will now carry on with Walter, who worked with Gillett for several seasons before they were on the Major League team together.
Together with the Tigers' athletic trainers and the rest of the medical staff, Gillett was part of a team that kept players on the field at a relatively strong rate. A FanGraphs story last fall listed the Tigers as the team with the second-lowest average of days lost to the disabled list from 2010 through 2013. This year was somewhat different; the Tigers suffered season-long injuries to shortstop Jose Iglesias, reliever Bruce Rondon and outfielder Andy Dirks, while missing Luke Putkonen for most of the season. Iglesias' injury dated back to his days with the Red Sox, who traded him to Detroit in July 2013.
All of those injuries involved younger players. Detroit's veteran players, meanwhile, stayed relatively healthy, save for two stints on the disabled list for Anibal Sanchez and a three-week DL stint for Joakim Soria. Both players' health will be key in 2015 for a Tigers team that doesn't have the starting depth it once did and needs all the bullpen help it can get.
Jason Beck is a reporter for MLB.com. Read Beck's Blog and follow him on Twitter @beckjason. This story was not subject to the approval of Major League Baseball or its clubs.