Broncos safety Justin Simmons says flagged hit that sent Jimmy Garoppolo to the sideline was legal

Justin Simmons says the hit he put on Jimmy Garoppolo Sunday was perfectly legal even though it resulted in a personal foul and sent the Las Vegas quarterback to the sideline for a concussion evaluation.

Simmons credited Garoppolo with a "great acting" job after the bang-bang play in which he initially appeared to hit the Raiders' new QB in the head in the first quarter of Las Vegas' 17-16 win.

On the game's opening drive, Denver outside linebacker Frank Clark was dragging Garoppolo down as he fought for the first down. Just as Garoppolo fell to the grass, Simmons crashed in and lunged at the QB.

Clips of the play show Simmons never hit Garoppolo in the head and that Clark actually bore the brunt of Simmons' hit. Garoppolo rolled over and held his head, however, and Simmons was flagged for a personal foul,.

The NFL spotter had Garoppolo removed from the game for a concussion evaluation and he missed two plays. The Raiders called a timeout on third-and-goal, allowing Garoppolo to get cleared, and he returned to the game and threw his first of two touchdown passes to Jakobi Meyers.

"I did see that, somebody sent me (the clip), a close friend of mine," Simmons said Wednesday. "I guess great acting on Jimmy's end. But if I get a fine … I think anyone who watches that clip can tell there was no force with the helmet. I hit his shoulder pad with my elbow and I think the rest of what I was aiming for, I ended up hitting either his back or Frank.

"Those types of plays are so bang-bang, critical third down. I'm not really sure how close the yardage was in real time," Simmons added. "I don't make the rules, but I don't think it was fine-worthy. If it was, I'm sure we'll do a good job with the appeal to that."

That was one of a half-dozen flags on Denver's defense in the opener.

The Broncos also lost Simmons' new sidekick at safety when third-year pro Caden Sterns tore his left patellar tendon while tackling running back Josh Jacobs in the first half,

The Broncos placed Sterns on injured reserve Wednesday, likely ending his season. They promoted wide receiver Lil'Jordan Humphrey from the practice squad to take his roster spot.

It's not like Simmons has to create chemistry anew with an inexperienced backup, however, because the next man up in this case is 14-year veteran Kareem Jackson, who had started alongside Simmons the last four seasons before he was beaten out by Sterns this summer.

"Yeah, that's super beneficial," Simmons said. "You know, there's so much that Kareem brings to the room in general. And, so, it's tough having Caden go down like that, and he was a big part of our plan defensively ... Now, as a collective whole, we're going to have to all step up and fill that void because the kid does a lot of things for us and that's a tough blow."