CARLTON talls Matthew Kreuzer and Levi Casboult have been put through a rigorous testing session on Friday morning as the Blues consider a shock return for the key pair. 

Kreuzer (knee) and Casboult (leg) were included in the 25-man squad to face Geelong on Sunday despite injuries that had been expected to sideline them for another three matches.

Both were put through a secret 20-minute testing session at the Power House Hockey Club in Albert Park on Friday morning before taking part in light handball drills. 

Coach Brendon Bolton said the pair would be put through more testing in the next 48 hours and the club would take no risks with them against the Cats.  

"They got through a good session this morning and we'll have another run in a day or two and see how we go," Bolton said.  

"It'll be more about jumping and landing and a lot of the specific work that the talls do.

"There's still 48 hours, but we're hopeful. 

"We'll just make an informed decision … based on medical advice and how they're pulling up from the sessions." 

Kreuzer was the hero of Carlton's fourth straight win two weeks ago, but he suffered a meniscus tear in that match and required keyhole surgery. 

After a follow-up with his surgeon, the Blues found that the ruckman had recovered quicker than expected from surgery.  

Casboult's inclusion on Thursday night was even more shocking after the Blues had ruled him out for up to two months with a hairline fracture in his left leg just 12 days ago.

"We went for a secondary CT scan and it was less of an injury than we thought," Bolton said.   

"The first scan revealed a bit more damage, but we had a CT scan that shows more detail.

"I think it's foolish of any club to just lock away a really long amount of time, because you're never totally sure." 

Bolton said both players had the mental toughness to play if there was any pain, but stressed the club would take no risks when it trimmed its squad to 22 to face the Cats.

Former Greater Western Sydney tall Kristian Jaksch shapes as a likely inclusion if either Kreuzer or Casboult are not passed fit.   

"He's got the potential to play at both ends, which gives you good flexibility," Bolton said of Jaksch, who is yet to play at senior level this season.