Sunderland boss Steve Bruce is desperate to get to the bottom of why Darren Bent keeps getting hurt on England duty, saying "it's not healthy".[LNB] Striker Bent missed England's midweek draw with Montenegro after he picked up a groin injury in training with the national team.[LNB]It is the third time that the former Tottenham and Charlton man has been injured while with Fabio Capello's side, and his club boss is at a loss to understand why.[LNB]"Your worst fear is getting the call saying he is injured. It is a shame for Darren because that is three times he has been with England and got injured," said Bruce.[LNB]"If you have a problem with a player, someone who has a bad back for example, you have dialogue with the England medical staff but you can't interfere with training games.[LNB]"I will be informing my medical department to have a word. If it happens once, fine.[LNB]"But if it has happened so often when he has been away with England then that is not healthy, especially as he has not even missed a training session since he has been here."