Raekwon McMillan was supposed to start at middle linebacker for the Dolphins Thursday.
He never got the chance.
McMillan got hurt covering his first punt as a professional.
The second-round pick injured his right knee when he collided with teammate Deon Lacey, stayed down on the field but ultimately walked off under his own power.
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McMillan, who didn’t take questions on his way out of the locker room, didn’t return to the game. He left the stadium on crutches, his knee immobilized by a brace.
The Dolphins had no update late Thursday.
A CBS-4 photographer who was on the sidelines for the Falcons game reported that McMillan tore his ACL and was out for the season.
When asked about that report afterward, Dolphins coach Adam Gase said: "You must have better sources than I do."
Meanwhile, safety Walt Aikens suffered a back injury at some point Thursday — believed to be pre-game — and was ruled out.