 Interim head coach Emmitt Thomas named Grimes the third cornerback on the depth chart, behind DeAngelo Hall and Chris Houston.On December 23, 2007, Grimes made his professional regular season debut and recorded a season-high 11 combined tackles (ten solo) during a 30–27 loss at the Arizona Cardinals in Week 16.He completed his rookie season in 2007 with 12 combined tackles (11 solo) in two games and no starts.