Thornton (undisclosed) did not participate in Sunday's practice, Sam Warren of The Athletic reports.
Thornton was present at the Raiders' facility doing work off to the side out of pads. The wide receiver missed Thursday's preseason opener against the Cardinals and will continue to miss valuable reps as he recovers from a minor issue. The missed reps allow Malik Benson and Jack Bech to extend their lead in the competition for the No. 3 receiver spot, with Benson in particular pulling ahead as he continues to see reps with the first-team offense.