Mullen will undergo toe surgery, and head coach John Harbaugh expects him to miss the season, Jeff Zrebiec of The Athletic reports.
The Ravens placed Mullen (toe) on the reserve/non-football injury list Friday.
Mullen (toe) was released by the Ravens on Friday with a non-football injury designation, Aaron Wilson of KPRC 2 Houston reports.
The Ravens placed Mullen on the active/non-football injury list Wednesday.
The Ravens claimed Mullen off waivers Monday, Field Yates of ESPN reports.
Mullen was waived by the Cowboys on Saturday.
Mullen (illness) was a full participant during Wednesday's walkthrough, Todd Archer of ESPN.com reports.
Mullen (illness) is listed as out for Monday's game at Tampa Bay, Michael Gehlken of The Dallas Morning News reports.
The Cowboys claimed Mullen off waivers Wednesday, Todd Brock of USA Today reports.
Mullen was waived by the Cardinals on Tuesday.