Texans coach Gary Kubiak told reporters Friday that running back Arian Foster and linebackers Brooks Reed and Bryan Braman will be game-time decisions on Sunday against the Dolphins. None of them practiced on Friday.

Foster left practice early Thursday due to a sore knee. He said he expects to play Sunday and described his injury as "around the knee area."

"It’s just kind of a vague description of where the center point of the pain is,” Foster said.

Kubiak said that Foster underwent an MRI on Thursday and everything was fine.

“I don’t know if it’s just the wear and tear of camp or whatever,” Kubiak said. “It got real sore on him. He feels better. I think if we pushed him to practice [Friday], he would have went out there and practiced. We’re going to be smart with him, but he’ll have to show us that he’s ready to go.”

If Foster cannot go, Ben Tate would get the start and Justin Forsett would be the No. 2 running back.

“Ben has had a great camp,” Kubiak said. “He’s been working really hard so if Arian is unable to go, this team knows that Ben will go in there and play well. Justin will play well.”

Reed left practice early on Thursday with a sore hip, and if he cannot play on Sunday, that means first-round pick Whitney Mercilus will see an expanded role in his first regular season game.

“I think Whitney is going to be fine,” linebacker Connor Barwin told reporters Friday. “He’s shown during camp that he’s more than capable. He was ready to rotate with us anyways. So if Brooks can’t go, which I’ll be surprised if he doesn’t, but [Mercilus] is more than ready to go.”

Kubiak also said that if Reed does not play, Jesse Nading would see his work load increase. Nading's role would also increase if Braman cannot play with a sore hamstring.

“All three of those guys will be game-time decisions,” Kubiak said. “I would say that Braman is close, very close, and the other two, I’m optimistic that they’ll be ready to go but we’ll have to see. We’ll look at [Saturday] and probably end up having to work them out before the game and see.”

Follow Texans blogger Sean Bielawski on Twitter, @CBSSportsNFLHOU.