Ball is not expected to practice this week while he recovers from the injury, which occurred during a non-contact play in Sunday's win over the Cardinals.
According to the Denver Post, an MRI done on Monday showed that Ball will not require surgery for the strain.
Ball had two carries for 11 yards against Arizona before sustaining the injury in the third quarter. He is Denver's leading rusher with 172 yards and a touchdown on the season, and has handled 55 of the Broncos' 99 total carries so far.
Ronnie Hillman is the team's next leading rusher, with 66 yards on 17 carries.
Ball previously underwent an emergency appendectomy at the beginning of training camp and missed two weeks of preseason.
The Broncos are 3-1 and in second place in the AFC West.
- Molly Geary