ENGLEWOOD, Colo. — As the Broncos entered their ninth day of training camp, the team was without several players as several veterans received rest days and wide receiver Diontae Spencer and linebacker Justin Strnad were sidelined.

After practice, Head Coach Vic Fangio said Strnad suffered some cramps on Friday afternoon and the team held him out to give him the time to recover. With Strnad and fellow inside linebacker Josey Jewell (groin) out with injuries, undrafted rookie Curtis Robinson received an opportunity to work with the first-team defense.  

"It's a challenge, there's no doubt about that," Fangio said. "But what's happened over the years is once they get it, they get it. … In the beginning, it kind of gets jumbled up for them, they don't exactly understand what we're looking for from technique and pickups, route pickups and run support. But … historically guys kind of just get it at some point and it all fits together, because everything we do fits together in its logic."

Spencer, meanwhile, had been working through some knee pain, Fangio said, and the team gave him the time off to recuperate.

"His knee's been up and down," Fangio said. "He's been practicing through it; we just felt he needed a day. I don't think he'll be out long."

They joined a growing list of players recovering from ailments including wide receiver Tyrie Cleveland (backside), nose tackle Mike Purcell (ankle), Jewell, defensive lineman Deyon Sizer (hamstring) and cornerback Mac McCain III (hamstring). Defensive lineman Marquiss Spencer also was not at practice after leaving midway through Friday's session. Many of those players worked with members of the training staff on a side field early in practice and later observed practice from the sidelines.

Veterans Bobby Massie, Justin Simmons and Kareem Jackson were given vet days and also observed practice from off to the side.