Before the season began, Matt Moore and David Garrard battled for the Dolphins starting quarterback spot, with rookie Ryan Tannehill more of an afterthought. But after Garrard hurt his knee, Tannehill ended up beating out Moore in training camp for the No. 1 role.
But after taking a sack from Jets linebacker Calvin Pace in the first quarter of Sunday's game, Tannehill left for good with what he termed afterward a hyperextended knee and a deep thigh bruise.
He told reporters in the postgame that he would undergo an MRI on Monday, but CBS Sports' Jason La Canfora reports the team doesn't think the injury is serious.
Tannehill was replaced by Moore (11-of-19, 131 yards, one touchdown), who helped lead the Dolphins to a surprisingly easy 30-9 win.
After he was injured, Tannehill ran on the sideline and worked on the exercise bike in an attempt to reenter the game -- he also was there in case of an emergency, because the team only had two active quarterbacks -- but thanks to Miami's special teams and defense, it wasn't imperative that he return.