The Broncos' backfield has been in motion since last season's leading rusher, C.J. Anderson, moved on to the Carolina Panthers. Anderson recorded a career-high 1,007 yards on 245 carries last season before signing a one-year, $1.7 million deal with the Panthers.
Booker resides ahead of rookie Royce Freeman, De'Angelo Henderson and rookies Dave Williams and Phillip Lindsay on the depth chart released by the team.
The 26-year-old Booker rushed 79 times for 299 yards and a touchdown last season while also reeling in 30 passes for 275 yards. He has 253 carries for 911 yards and five rushing scores since being selected with by the Broncos with a fourth-round pick of the 2016 NFL Draft.
Freeman was taken in the third round of the 2018 NFL Draft after setting multiple school records at Oregon, including career rushing yards (5,621), all-purpose yards (6,435), total touchdowns (64) and rushing touchdowns (60).
The 6-foot, 229-pound Freeman rushed for 1,475 yards and 16 touchdowns last season after an injury-plagued junior campaign. His career rushing yardage is the second-most in Pac-12 history behind former USC back Charles White (6,245).