"It's hard for me to give you an answer right now," Texans coach Gary Kubiak said. "He's going to miss some time. I don't know if that's three or four days. I don't know if that's a few weeks.
"We're dealing with a hamstring, we know that. We're still in an evaluation process. We're going to get a couple different opinions over the course of the next two days. Once we get a better evaluation and see how he progresses over the next two days, I can probably answer your question better."
Johnson is considered unlikely to play Sunday against the Oakland Raiders.
Jacoby Jones would start in his place.
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