Dave Duncan intends to step aside as Cardinals pitching coach in order to deal with personal matters related to his wife Jeanine's ongoing battle against cancer.

The club is expected to announce no later than Monday Duncan's intention to relinquish a position he has held with the Cardinals since October 1995 and within the major leagues since 1982, making him the longest-tenured pitching coach in the game's history.

Duncan will remain with the club in another capacity, according to club sources, but recently decided that his commitment to Jeanine's treatment would prevent him from devoting the time necessary to carrying out the detailed responsibilities he considers essential to the position.

Reached Thursday night, Duncan declined comment until the club issued a formal announcement.