Boston Celtics assistant general manager Mike Zarren is a serious candidate for the Sixers general manager position, sources with knowledge of the search told SI.com.

With incumbent Rod Thorn expected to transition to a consultant role once his replacement is found, the Sixers were reportedly deciding between former Portland assistant general manager and ESPN analyst Tom Penn and former New Orleans general manager Jeff Bower. Penn was considered the frontrunner just weeks ago, but sources say his candidacy has taken a serious hit while Zarren and Bower continue to jockey for the job.

via Sam Amick of Sports Illustrated