Mike McGlinchey says it will be "impossible" for the San Francisco 49ers to replace Trent Williams after he suffered an ankle injury during an 11-10 defeat to the Denver Broncos on Sunday.

Left tackle Williams did the damage when he was blocking Broncos defensive end Bradley Chubb during the third quarter and Denver defensive lineman D.J. Jones fell across his right leg.

On the same play, quarterback Jimmy Garoppolo stepped out of the end zone for an ultimately costly safety.

Niners head coach Kyle Shanahan revealed after the game nine-time Pro Bowler Williams, who was replaced by Jaylon Moore, was likely to have sustained a high right ankle sprain.

Right tackle McGlinchey said: "[Trent is] as important to our football team as anybody is. Colton [McKivitz] stepped up, and he's had an unbelievable last year and some change, and he's ready for that.

"Jaylon Moore is capable of playing in that role. We have guys to fill the spot, which is a good thing; but obviously, it's impossible to replace a Trent Williams, and that hurts our football team, for sure."

Garoppolo said: "It's tough. Trent's a warrior. Hopefully, he bounces back fast, but it's always tough when you lose a guy like that, especially the leadership that he brings to this team.

"The poise and everything that he brings, it will be tough to replace that. But we've got to."

Shanahan felt the 49ers could have no complaints after a loss at Empower Field at Mile High that left them at 1-2 early in the season.

"We had our opportunities, but we definitely didn't do enough offensively in the second half," he said.

"I thought we made way too many mistakes. We had our opportunities in the first half, where I thought we should have been a lot more than we were.

"We missed those. Came back in the second half and I thought the defense kept it going, offense had a chance early and started out with a fumbled snap, then we never got it going after that."