Glasnow has not been observed at any of the Rays' summer camp workouts at Tropicana Field, Juan Toribio of MLB.com reports.
Glasnow was reported to be ready to take on a regular-season workload in the days leading up to summer camp, but he's now apparently been a non-participant for four days. The towering right-hander is due for a prominent rotation role in the coming season, although it remains to be seen if his ongoing absence is ultimately illness-related.