This, following a second operation which will only rule him out for two months.
The former Brighton defender had major surgery and missed most of last season after suffering cartilage damage but on his return to the line-up the injury got worse before he underwent a clean-up operation last week.
"It was good news for me," Virgo told the Bristol Post.
"The problem was nothing more serious than a reaction from my previous operation. There were a few loose fragments floating about inside, so I've had the knee cleaned out.
"It is frustrating, but it could have been a lot worse. There was a stage when the doctors thought the problem might have been a lot more serious.
"That was a worry. I've got a wife and family and a lot of things went through my mind during what was a short period of uncertainty.
"The knee wasn't 100 per cent right and it gradually started to get a lot more uncomfortable for me with every game I've played. Some days I was struggling to walk to the toilet after games."