By Dan Ambrose: Next week Robert Guerrero will be undergoing arthroscopic surgery to repair a torn left rotator cuff. Dr. Michael Dillingham says there is a slight tear to his left rotator cuff. However, there would be additional damage to the shoulder that the previous MRI failed to show that could be troublesome for Guerrero.

Right now the estimate is four to six months for Guerrero to heal up and make a comeback. But if there’s other damage to the shoulder than it could be even longer. As it is it’s difficult to say whether Guerrero will ever regain the full strength and flexibility in the shoulder. A tear to the rotator cuff is a very serious injury and when it affects the fighters main punching side like it does with Guerrero, who is a southpaw, it can be even more problematic.

Guerrero has good enough boxing skills to remain an effective fighter but if you take away his power, which was mainly in his left hand, it makes him a lot more vulnerable against opposition. It would be difficult for Guerrero to compete with the best fighters at light welterweight without any power to speak of. Without power, Guerrero would be a sitting duck for some of the bigger punchers in the division.

He might better off moving back down to light weight or super featherweight if doesn’t regain the strength in that shoulder. It would be bad for Guerrero to face guys like Marcos Maidana, Breidis Prescott or Lucas Matthysse with the power that he once had in his shoulder. He’d take a beating against all those guys without power.