Arizona Cardinals' star running back David Johnson was forced to leave Sunday's 35-23 loss to the Detroit Lions after suffering a wrist injury following a big hit in the game. According to Pro Football Talk, X-rays on his injury came back negative, though he'll have an MRI Monday to further assess the injury.
ESPN's Adam Schefter and Chris Mortensen added that the MRI "will determine whether Johnson will miss a 'few weeks' or 'half the season or more' with a sprained wrist."
With Johnson's status unclear going forward, however, it leaves Kerwynn Williams as the team's starter and fantasy owners questioning if he'll be worth adding on waivers next week.
Williams didn't do much with his limited opportunities on Sunday, rushing five times for just 10 yards, though he did add a touchdown. He also had a reception for two yards. And the Cardinals struggled to gain any traction on the ground in general, rushing 18 times for a measly 45 yards.
That's worrisome for Williams' status going forward, as he isn't nearly as dynamic a runner or receiver as Johnson. To his credit, few players are as productive as Johnson, but Arizona's disappointing performance in the run game on Sunday makes Williams a far less appealing backup than other handcuffs might provide around the NFL.
As long as Johnson is out of action, Williams should absolutely be owned in all formats. And he does have some upside—in three seasons and 21 games played, he's produced an impressive 5.6 yards per carry, albeit on just 98 attempts.
So it's safe to call Williams a flex option, especially in favorable matchups, with the room to grow into the RB2 range if he produces in his starting role and the Cardinals utilize him as a true feature back. Next week's matchup at the Indianapolis Colts is a decent one for Williams if you have a need at your flex spot this early in the season.
In general, however, fantasy owners should be cautious about inserting him into their starting lineups.