Shortly after, the club issued a formal release stating that Duncan has taken an indefinite "leave of absence to attend to his wife Jeanine as she continues her treatment and rehabilitation..."
Jeanine Duncan underwent surgery to remove a brain tumor in August. Her husband left the Cardinals at that point. He turned over the coaching reigns to bullpen coach Derek Lilliquist until returning for the conclusion of the regular season and all of the playoffs.
The change would rock the stability of new manager Mike Matheny's first staff. At this point, it is not clear if Lilliquist will again step in or a permanent replacement will be hired. Duncan is under contract for 2012 and the team holds a 2013 option on his services as well.
Duncan was Tony La Russa's pitching coach for the last 28 years, first with the White Sox, then Oakland. They joined St. Louis together prior to the 1996 season.
Duncan, known for rejuvenating many a pitching career, has been associated with eight Cy Young Award-winning hurlers during his MLB-record 32 years as a pitching coach and caught four others as a player.
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