Rams WR Cooper Kupp leaves practice early with hamstring injury

Kupp sustained an apparent hamstring injury and exited practice early.
The Rams are uncertain how long Kupp will be sidelined.
Kupp missed the final eight games last season due to an ankle sprain.
In 2021, Kupp won the NFL's receiving triple crown for catches, yards and touchdowns.
Kupp is expected to be QB Matthew Stafford's top target this season.