Carlton could regain Chris Judd and Troy Menzel for Friday night's blockbuster against Collingwood at the MCG.

Judd missed the win over the Saints with a stiff lower back, while Menzel has missed the past two matches with a calf injury – both players will be tested at training this week.

Meanwhile new recruit Mark Whiley could be in contention to make his debut.

Whiley was named in Carlton's squad for Round 4 but was a late withdrawal after hurting his hamstring at training.

The news is not as good for Irishman Ciaran Byrne who also injured a hamstring at training, just a week after making his AFL debut.

Carlton's Head of Football Andrew McKay says Byrne will be out for three weeks.

"Ciaran Byrne strained his hamstring at training last week, which was devastating for him and us given his parents over watching him play," McKay said.

"It's a reasonable hamstring injury and he will be out for three weeks which is disappointing for both parties."

Dale Thomas is still approximately three weeks away, but big man Matthew Kreuzer is a chance to make his long-awaited return from injury through the VFL.

Injury List

Byrne (hamstring) 3 weeks
Giles (foot) indefinite
Judd (back) test
Kreuzer (foot) test
Menzel (calf) test
Sheehan (groin) 1-2 weeks
Thomas (shoulder) 3 weeks
Whiley (hamstring) test
White (knee) 3 weeks