GREATER Western Sydney have refused to rule Josh Kelly out of Saturday night's semi-final clash with Collingwood at the MCG, but the star midfielder remains a long shot to recover from a knee injury in time to play.

Kelly limped from the ground late in the opening term of the Giants' 49-point win over Sydney on Saturday and despite having his knee strapped and tested, he played no further part in the game.

The club champion and 2017 All Australian failed to train with the Giants' squad on Tuesday.

He would be a massive loss if, as expected, he isn't passed fit to take on the Magpies in Melbourne, but GWS head of athletic performance David Joyce said Kelly is still a chance. 

GET TO THE GAME All your finals ticketing info

"Josh has got a pre-existing lateral meniscus issue that he manages beautifully," he said.

"The meniscus is the shock absorber for the knee and on the weekend, he had a twisting incident which has aggravated it. We tried to see if he could function and we just decided it wasn't worth risking him. 

"He has actually presented really well over the last couple of days, he's walking around the club and he's doing everything to be right for this weekend. 

"We're going to give him every opportunity, he's obviously very important to us, we expect him to improve day by day and we'll give him every opportunity for this week."

The Giants have Ryan Griffen ready to come in should Kelly not play this week, after the veteran trained solidly on Saturday to put his hand up for a recall.

Griffen hasn't played since he suffered a hamstring injury in round 22.

"Ryan would have been effectively available to play last weekend, we just wanted to increase his loads and he's ticked every single box," Joyce said.

"He's sprinted and had an outstanding 10km+ session on Saturday, so he's locked and loaded and ready to be selected this weekend."

Key defenders Aidan Corr (groin) and Sam Taylor (hamstring) are both an outside chance to be available for the Collingwood clash, while ruckman Dawson Simpson (ankle) has made a remarkable recovery from his injury and could make a shock bid to take on All Australian Brodie Grundy.