Jones was not included in the defending champions' squad last week as he recovers from shoulder surgery.
Dan Biggar was named captain for the tournament in the absence of the inspirational lock, who did the damage in a 54-16 thrashing against New Zealand in October.
Jones incredibly recovered from a dislocated shoulder to skipper the British and Irish Lions in South Africa last year.
Wales head coach Pivac says Jones is unlikely to play in the Six Nations, but there is a chance the 36-year-old could feature.
"Never say never," Pivac said, adding: "It's Alun Wyn Jones. I probably wouldn't enter the conversation if it was anyone else, but the guy has broken so many records.
"I honestly say that, I would never say never. But look, it'll be a long shot. Let's just say that.
"Al is working incredibly hard behind the scenes, as you know he would, to get himself in the best shape possible for either the Ospreys or Wales."
Stand-in captain Biggar echoed Pivac's sentiments as the holders prepare for their opening match against Scotland at Murrayfield on February 5.
"I wouldn't put my mortgage on it," the fly-half said.
"I don't think any of us expected [Jones] to turn up in South Africa in the summer, and he managed to get on the plane.
"If there is anybody who has got a chance of being fit for some part of this tournament, then Al is probably the man. I wouldn't rule it out just yet."