The 30-year-old limped out of the Grecians' 1-1 draw with Torquay earlier this month with a hamstring tear and the former Cork man has shown his determination to return to full fitness as soon as possible.
O'Flynn, who has scored 11 times this season, visited a cryogenic chamber while at home in Ireland and has made every effort to speed up his comeback.
And City manager Paul Tisdale, who signed the striker following his departure from Barnet in 2011, was quick to praise O'Flynn's professionalism and dedication to the cause.
"He was due to go back to Ireland anyway but he is so incredibly professional that I had no hesitation telling him to have the week at home," Tisdale said.
"He is going to be out for six to eight weeks so he isn't going to miss out on anything here and he made sure he found somewhere where he could replicate the treatment he would get here.
"We have a squad of players like John, I don't even have to check. It is not a case of keeping a rein on these chaps, they are so keen to do well and so professional that I don't think you have to ask.
"He will just do the right thing, I know he will."
- Sports & Recreation
- Paul Tisdale