Bell signed a contract for a boxing match July 30 against fellow NFL running back Adrian Peterson, ESPN's Mike Coppinger reports.
Bell hasn't announced his retirement, but this can be taken as a sign that he either isn't focused on his football career or else isn't getting opportunities. It's possible his brief stint with the Bucs at the end of last season will be Bell's final NFL action, as he's now 30 years old and a half decade removed from his Pittsburgh peak (2014-17).