Chicago Bears tight end Zach Miller and wide receiver Eddie Royal have been diagnosed with concussions and will be required to go through the league's mandated protocol before returning to training camp, ESPN.com reported on Monday.
Miller participated in practice on Sunday before experiencing symptoms while Royal prematurely exited Monday's practice.
"(Miller) felt a little funny last night and didn't feel as good this morning, so we just shut it down," coach John Fox said. "He'll go through the NFL's concussion protocol."
With fellow tight end Martellus Bennett now in New England, the 31-year-old Miller is expected to improve upon his totals from last season when he reeled in 34 receptions for 439 yards and five touchdowns.
The 30-year-old Royal had 37 catches for 238 yards and a score in his first season with the Bears in 2015.