Mayfield (thumb) wasn't spotted at practice Thursday, Greg Auman of Fox Sports reports.
Mayfield has yet to practice or play since sustaining a thumb injury late in Tampa Bay's Week 3 loss to the Vikings. He looks to be headed for a third consecutive absence Sunday against the Steelers, which would pave the way for Jalon Daniels to remain in the starting role under center. Daniels guided the Buccaneers to a win over Dallas in Week 5 after losing to the Packers in Week 4.