Third-year tailback Ronnie Brown, who has represented the bulk of the Miami Dolphins' offense so far in 2007, will undergo an MRI exam Monday morning to determine the extent of a right knee injury that forced him from Sunday's 49-28 loss to the New England Patriots. Brown was injured in the third quarter while attempting to make a tackle on an interception return by Patriots' cornerback Randall Gay. An X-ray on Sunday afternoon was inconclusive, but Brown's right knee was immobilized by an air cast and he walked through the locker room on crutches. The initial diagnosis announced by the team is a sprained knee. But coach Cam Cameron said the MRI would be utilized to provide a more precise determination of the injury.