Thielen (ankle) is dressed for Friday's practice, Darin Gantt of the Panthers' official site reports.
There was no report of any issue prior to Wednesday when Thielen was listed as a limited participant on Carolina's first injury report of the season. Concern grew Thursday when he was a non-participant, but his return Friday morning suggests the 33-year-old still hopes to play Sunday at Atlanta. DJ Chark (hamstring) and Terrace Marshall (back) also are on the Week 1 injury report, with Chark in particular appearing in danger of missing the season opener.