The Blues midfielder limped off the St Andrews pitch 65 minutes into the FA Cup 4th round tie against Wimbledon with a recurrence of the hamstring injury that kept him out of Blues' last Premier League game at Chelsea earlier this month.
Dunn himself has confessed that he may have rushed his comeback from the injury he sustained in the 2-1 win against Southampton on January 10th and says his chances of facing Sir Bobby Robsons side at St. Andrews this weekend are doubtful.