Alabama running back Bo Scarbrough tore his ACL during a scrimmage Friday, underwent surgery Monday and started rehab Wednesday.

It’s a remarkable sequence that would have been impossible just one decade ago.

Will we eventually get good enough at ACL surgeries that those who tear the most important knee ligament in spring practice can feel good about being able to start the season in the fall?

We’re not to that point yet medically, but Scarbrough’s quick progress is impressive nonetheless.

Check out video of the freshman running back rehabbing his knee.

Alabama’s backfield is thin without Scarbrough. Altee Tenpenny elected to transfer after last season, and Tyren Jones, already suspended indefinitely, got kicked off the team after an arrest for marijuana possession last week. T.J. Yeldon and fullback Jalston Fowler are headed to the NFL draft.

Derrick Henry, Kenyan Drake and true freshman DeSherrius Flowers are practicing at running back right now, and five-star signee Damien Harris will join the team this summer. Still, it’s a major bummer for Alabama coaches, players and fans to watch Scarbrough, an exciting young talent, go through this injury.