Today's workout will be the Sixers' fourth announced predraft workout and the first involving a center: Mullens, 20, is a 7-footer who played one season at Ohio State and averaged 8.8 points in 20.3 minutes per game. Mullens is projected as a middle first-round selection because he might need at least a couple of seasons to develop.

Ayers, a 6-7 guard, played four seasons for the Fighting Irish and averaged 11.1 points per game during his senior season. Ayers might not be drafted in either round.

Sixers president and general manager Ed Stefanski has said the team is focused on selecting a perimeter player.

The Sixers currently have only two guards under contract: Willie Green and Lou Williams. Last season's starting point guard, Andre Miller, is an unrestricted free agent. The Sixers are allowed to contact Miller on July 1, the opening day of NBA free agency.

Mullens aside, the Sixers' predraft workouts have been composed almost entirely of point guards and shooting guards.

This draft is guard-heavy. Five point guards - Ty Lawson, Eric Maynor, Jeff Teague, Jrue Holiday, and Darren Collison - might be available when the Sixers select at 17.

Lynam coming back. A source close to the Sixers confirmed that new head coach Eddie Jordan will retain assistant coach Jim Lynam, who has been an assistant with the Sixers since 2005-06 and worked with both Maurice Cheeks and Tony DiLeo.

Lynam joins Mike O'Koren and Aaron McKie on Jordan's staff. One assistant coaching position still remains vacant. Another source close to the situation said this last assistant spot would not be addressed until after July's rookie summer league in Orlando, Fla.

Contact staff writer Kate Fagan at 856-779-3844 or kfagan@phillynews.com.