THOUSAND OAKS, Calif. -- Malcolm Brown, Todd Gurley's backup at running back, injured an MCL in the second half of Sunday's win and is "going to be out for a little bit of time," Los Angeles Rams coach Sean McVay said after Wednesday's practice.

Brown's absence could open a role for Lance Dunbar, who is still officially on the physically unable to perform list but has been able to practice with the team since the start of last week.

The Rams have yet to decide whether Brown will require surgery on the knee, but they're seemingly prepared for this to become a long-term injury.

Brown has gained 138 yards on 37 carries and has scored two touchdowns, one of which came after recovering a blocked punt.

The Rams also have Justin Davis, an undrafted free agent out of USC who ran well during the preseason but was prone to fumbles. Tavon Austin, the Rams' high-priced gadget receiver, has acted like a running back while presenting the threat of jet sweeps.

Dunbar, who spent the previous five years with the Dallas Cowboys, was brought in to be something of a change-of-pace back and was hoping to fill a role similar to the one Chris Thompson played for McVay's Washington Redskins offense, as someone who specialized in catching passes out of the backfield.

McVay will use the rest of the week to determine whether Davis or Dunbar will take Brown's place behind Gurley, who ranks third in the NFL with 190 touches. The Rams can leave Dunbar on the PUP list through the end of next week before having to make a determination on his status.