David Montgomery, Phillies chief executive, has taken a medical leave of absence from the team.
The team announced Thursday that Montgomery, 67, will return to his duties when he has made a full recovery from his cancer treatments.
In May, Montgomery had cancerous bone removed from his jaw and replaced with bone from one of his legs.
Former Phillies General Manager Pat Gillick will run the team's day-to-day operations.
Gillick said in a news release that he is "glad to be of assistance to the Phillies."
Montgomery, a Roxborough native has worked for the team for more than 40 years. He currently serves as general partner, president and chief executive officer.
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