Courtland Sutton is done for the season due to a knee problem and Drew Lock will miss up to five weeks with a shoulder injury, Denver Broncos coach Vic Fangio confirmed on Monday.

Both players were injured in Sunday's Week 2 defeat to the Pittsburgh Steelers, when the Broncos went down 26-21 to slip to 0-2 and finished the game without quarterback Lock and wide receiver Sutton.

The QB went down on Denver's second drive and did not return. The injury to Lock's throwing shoulder will cause him to miss "three to four to five weeks, all dependent on the healing process".

Fangio added: "He just got a bad bruise there, and when it's your throwing shoulder, it's going to take time to heal.

"It's got to calm down, get his strength back to where he fully has it and he can operate at 100 per cent."

The outlook on Sutton was even worse after he attempted to tackle Steelers cornerback Joe Haden following an interception in the second quarter.

Sutton had been questionable with a shoulder injury heading into the game but will now sit out the rest of the year due to a knee issue.

However, Fangio did not blame Sutton for attempting to halt Haden, explaining: "When those guys are out there playing, they're playing on instincts. They're playing on experience.

"They intercepted the ball. It's Courtland's instincts and natural reaction to go and try and tackle the guy. I don't know that you can get around that."

As the Broncos plot how to move forward with their season given their latest injury setbacks, Fangio was asked if Colin Kaepernick - the former San Francisco 49ers quarterback who has been out of the league since his protests against racial injustice and police brutality - was an option to replace Lock.

"His name hasn't come up in the brief discussions I've had with John [Elway] at this point," he said.

"I'm sure John and Matt [Russell] will work hard to bring somebody in here that they think will be the best fit."