GIANTS co-captain Phil Davis is no guarantee to run out in Saturday night's clash with Sydney after he failed to train with the rest of his teammates at the SCG on Friday morning.

Davis rolled his left ankle in the final quarter of last week's loss to Fremantle, but despite what looked to be a nasty injury, the key defender was named in the GIANTS' team to take on the Swans.

The GIANTS 22 selected on Thursday, along with emergencies Jackson Hately, Isaac Cumming and Matt Buntine, had a light skills session on Sydney's home deck the day before the match, but Davis was an onlooker.

GIANTS coach Leon Cameron said Davis was expected to do some work on his own later on Friday ahead of a decision on his availability to take on Sydney superstar Lance Franklin on Saturday.

"He's not 100 per cent over the line but he has surprised us in a good way," he said.

"He's done some running and change of direction and he's kicking the footy.

"We'll make a call when he ticks some more boxes.

"We've been really aggressive in the past and put players out there that perhaps at 85 per cent (fit), and I've got no doubt Phil could do that, and he has done in the past.

"But as we've said all along if we don't think he's close to 100 per cent, especially when you're dealing with the quality forwards they have, we'll make that change."

If Davis is ruled out of the clash, Hately is his likely replacement, after he was dropped despite a promising 22 possessions on debut against the Dockers.

The GIANTS picked Aidan Corr on Thursday to cover their defensive posts, which would allow Hately's talents to add run to the visitors' midfield depth.

Corr (groin) returns for his first game since round 17 last year, with star forward Toby Greene also back for his second match of the season.

Greene played in the GIANTS' round one demolition of Essendon, but pulled up sore with a calf problem and hasn't been seen since.

Cameron said the 2016 club champion would play his usual role in the forward line against the Swans, but once he can play some games consistently without any injury worries, a return to the midfield could be in his future.

Similar to the way Collingwood uses Jordan De Goey to pinch-hit as an onballer during games, Cameron said Greene, who started his career as a ball-winning midfielder, could do the same for the GIANTS.

"We really want to get him back in there for a few minutes at a time because of his explosiveness and his competitiveness, and every side has one or two players that have that impact," Cameron said.

"He's got that ability to play onball and I don't think he's ready for that yet, but if we can get him up and going, hopefully we can look at that.

"We discussed it over the pre-season, because he can get that release from a hard defender who is on you all the time and get a bit of freedom."