Earlier this week, San Francisco declined to renew the contract of Al Everest, who took over the job from Mac Duff in 2007. Upgrading the Niners' return game is among Singletary's offseason priorities after the team struggled in that area all season. The unit was last in the NFL in average punt return yardage.
Mac Duff, 61, went from the 49ers to co-defensive coordinator at Texas for one season in 2007 and most recently was defensive coordinator for the Las Vegas franchise of the United Football League.
The team wouldn't say Friday when Mac Duff interviewed.
Copyright 2010 by The Associated Press