It's a scary sight for any NFL team and its star player - in this case, the Houston Texans and star wide receiver Andre Johnson.

Johnson caught a pass in the second quarter for 10 yards and went down untouched. He ended up walking off with a limp on his own power before heading to the Texans' locker room.

The fear is a knee injury, potentially of the season-ending variety. But Johnson's injury does not appear to be that serious, according to reports. He will have an MRI on Monday, but Texans head coach Gary Kubiak said after the Texans' 17-10 win over the Steelers on Sunday that the injury is hamstring-related. The Texans later diagnosed the injury as a strained hamstring.

Johnson did not speak with reporters after the game.

The way he went down was deflating, Kubiak told reporters after the game, because it was like he just got shot, and that scares the heck out of you. It's very difficult. He's the leader of our team and has been the leader of this franchise for a long time.

With Johnson gone, Jacoby Jones replaced him in the Texans lineup on the other side of Kevin Walter. Neither of those two receivers caught a pass.

The Texans will find out more Monday. But if Johnson will miss a significant chunk of time, it will mean a huge headache for Kubiak, as evidenced by Johnson's replacements Sunday.

If we have to go without him for a period, Kubiak said, we're going to have to ask some guys to really step up to the plate.