Green's concussion was diagnosed as grade three, the most severe, and he'll undergo further tests to determine his future. He has been ruled out of Sunday's game at Cleveland, and Cameron declined to discuss the possibility the injury will force the 37-year-old Green to retire.
"I don't think we really know the full extent, because there are some ongoing tests," Cameron said. "Right now I just think there are too many unknowns."
Cleo Lemon, who replaced Green at Houston, will make his second NFL start against the Browns. Second-round draft pick
John Beck becomes the backup.
The loss of Green is another blow in a season where little has gone right for the winless Dolphins and their first-year coach.
Miami and St. Louis are the NFL's only 0-5 teams. The Dolphins were beaten 22-19 Sunday on a last-second 57-yard field goal, extending their losing streak to eight games over two seasons, which matches the franchise record set in 1967.
"When you're losing, it's a struggle," kicker
Jay Feely said. "It's tough to come in to work. It's tough to work hard. You find out a lot about the players on your team, because you see the guys who are going to quit, and the guys who are going to keep working hard."
The latest loss was mitigated by relief that Green wasn't more seriously hurt.
He took a knee to the head blocking 315-pound tackle
Travis Johnson on an end-around, then crumpled to the ground. Teammates kneeled in prayer while medical personnel revived Green, and he was strapped to a stretcher before being carted away to a hospital.
But he flew home with the team, and Feely said it was difficult to tell he had been hurt.
"I was amazed at how well he felt and how coherent he was," Feely said. "He was talking the whole way on the plane flight home." Still, Green's second concussion in 13 months leaves his return in doubt.