It has not been confirmed that the failed physical is why McDonald was cut, although multiple media reports say McDonald was released with a "failed physical" designation.
Report: McDonald failed physical (Comcast SportsNet New England): It is being reported that the... http://t.co/VK8W7bN26b #Patriots #NFL
— Patriots News (@Track_Patriots) August 1, 2013
This cut comes as a huge surprise to Patriots fans, as McDonald had a great year with the Pats last year, as he started four games but player in twelve altogether, providing much needed help in the offensive line. McDonald had health problems throughout the year, and started the year on the PUP (Physically Unable to Perform) list. Once he was back at camp, he made some progress when working with the OL in the red zone. The Boston Herald also states that he may be able to return to the team once his health improves