One of the big concerns for the Bears offense entering Sunday’s game against the Raiders was the loss of running back David Montgomery, who suffered a knee sprain in a Week 4 win over the Lions and is expected to be sidelined 3-5 weeks.

While there was plenty of confidence in Damien Williams and rookie Khalil Herbert to step in for an injured Montgomery, they certainly exceeded expectations and were a big reason for the offense’s success in a 20-9 upset win against the Raiders.

Williams and Herbert combined for 34 carries and 139 rushing yards and a touchdown with both averaging more than 4 yards per carry. Herbert led the Bears with 18 carries for 75 yards and Williams added 16 carries for 64 yards and a score.

“I know [Montgomery] is at home now watching this and he’s proud,” said head coach Matt Nagy. “For Damien Williams to step up and have 16 carries. For Khalil Herbert to come in as a rookie and run the ball like he did — that’s impressive.

“It talks to the offensive line and the tight ends. It talks a lot to those running backs. It talks a lot to our coaches for getting those guys ready. I think you guys [reporters] would probably agree there’s a little bit of an identity going on right now.”

While Williams has found success like this in the past with the Chiefs, this was Herbert’s first significant action as a rookie, and his performance was surely promising.

“Man, I was telling him all game — especially coming out in the second half — ‘This is on you now,’” Williams said. “I gave my first blows in the first half. Now it’s your turn to get your blows in.’ As a young kid coming into this environment, he held himself great.

“He’s a very consistent person and I feel like if he continues to do that, he’s going to have a long, long future.”

While the loss of Montgomery still looms large, the Bears are certainly in capable hands with Williams and Herbert in the run game.