Broncos RB Mike Boone out four to six weeks with quad injury

The Denver Broncos continue to hold a quarterback competition between 2019 draft pick Drew Lock and veteran Teddy Bridgewater. Both of those signal-callers will be without a key offensive contributor, likely for all of the preseason. 

As Myles Simmons noted for Pro Football Talk, Denver running back Mike Boone went down to a quad injury during Thursday's joint practice with the Minnesota Vikings ahead of Saturday's preseason game between the squads. Boone does not need surgery to repair the issue but is expected to miss anywhere between four and six weeks, which suggests he'll be shut down through at least the remainder of the month. 

Boone was already behind veteran Melvin Gordon and second-round pick 

Javonte Williams on the depth chart, but ESPN's Jeff Legwold noted last week that all three ball-carriers worked with offensive starters in practices. 

Across his three seasons with Minnesota, Boone rushed for 379 yards and four touchdowns before signing with Denver as a free agent in March.

Meanwhile, Lock will start over Bridgewater at quarterback for Saturday's game. Bridgewater, however, will get the start against the Seattle Seahawks on Aug. 21.