GARY Ablett's 300-game milestone is on hold for at least a week with a calf injury ruling the superstar Sun out of Sunday's match against St Kilda.

Ablett sustained a calf injury in last Saturday's match against Carlton and failed to pass a fitness on Friday, despite completing his rehabilitation all week.

Suns football manager Marcus Ashcroft said it was a disappointing outcome for all involved.

"Really disappointing for Gary, his family and the footy club – waiting for his much anticipated 300th game," he told the club's website.

"Gary hurt his calf in last weekend's game, he had been rehabbing it all week."

"Unfortunately, today trying to complete some rehab runs, didn't get through those at all. 

"He'd been working really hard the last few days, we know he's the ultimate professional, and he did everything he could."

The shock decision is understood to have been made on Friday after consultation with the medical staff, who decided no risk should be taken with Ablett.

AFL.com.au understands it's too early to tell at this stage whether Ablett will miss more than a week due to the injury, with the club describing the champion's injury as a 'niggle'.

The dual Brownlow medallist remains a key player for the Suns as they attempt to make the finals for the first time.

Kade Kolodjashnij has also been withdrawn from the team.

Josh Schoenfeld and Trent McKenzie have been added to the 25-man squad.

The Suns lost Aaron Hall (hamstring) and Brandon Matera (foot) to injury during the week, as well as a season-ending leg injury to Michael Barlow.