The 39-year-old damaged some cartilage in the Highlanders' opening game of the season late last month.
He felt something ''pop'' while tackling Liaki Moli midway through the first half of his side's 29-21 win against the Blues and was expected to miss up to a month of rugby.
But we are not talking about a mere mortal.
The veteran lock has made steady progress during the Highlanders' bye week and coach Jamie Joseph rates him a 70-30 chance of playing in the home fixture against the Force this Saturday night.
''He is coming along well,'' Joseph said.
''He trained today so we just have to see. He is going to have another scan tomorrow or the next day to see how it is healing.
''I probably rate him a 70-30 chance of making it. But he has to have a scan and see how he goes.''
Winger Patrick Osborne is still ''no good''.
He was struggling with an ankle complaint and is only a 50-50 chance of playing.
Joseph was keen to protect Popoali'i's privacy but confirmed the medical procedure had gone well.
''One thing I can tell you is he has had a successful operation. He has come out of that but his [rugby] future is yet to be decided but only because I need to confer with our medical team.''
Meanwhile, Joseph said the bye week, while perhaps not ideal timing, had been valuable all the same.
''Basically, the guys had a bit of a breather. We've had five games -two and three in the pre-season - so it was good to have a break.
''But you have a bit of momentum and you want to carry on. But we don't control the competition structure and we knew about it six months ago so we planned around it. That is the best we could do.''
The Highlanders should be in for a tough return with the Western Force impressing with a comprehensive 32-7 win against the Melbourne Rebels in Perth on Saturday.
''They've beaten us the last two times. They're very strong up front, they have very big backs and they scored, I think, four tries in the first half against the Rebels.
''All of those things suggest they are going to be a difficult opponent.''
