ST KILDA star Jack Sinclair has indicated he won't be available for the Saints' opening game of the season against Geelong, but he's confident he'll return for their round two game against Collingwood.

Sinclair has been managing a calf injury and said scans on Wednesday would help determine his return to play.

The dual All-Australian says his rehabilitation is on track, but stopped short of saying he'll be fit to face the Cats on March 16.

"It's hard to say. The five-day break (between rounds one and two) probably doesn't help me," Sinclair said at St Kilda's Moorabbin headquarters on Tuesday to promote the round-two clash, which will be the annual 'Spud's Game' in honour of late Saints star Danny Frawley.

"I'll get a scan on Wednesday and reassess, see what the coaches think.

"It's a long year. Round one, there's such a big build-up and you want to be there but there's a bunch of other games to look to. I've missed my fair share of round one games over my career so I'm not too fussed to be honest. Most of those were due to selection though."

Marcus Windhager is also in a race against the clock to be ready to play the Cats, while Hunter Clark is facing up to six weeks on the sidelines after injuring his calf.

Windhager, who broke his other hand in a practice match 12 months ago, underwent surgery this week after breaking his left hand during last week's match simulation against Essendon.

Despite the Saints' hopes it wouldn't delay his start to the season, the 20-year-old is no guarantee to play in the Saints' season opener.

"Marcus will be touch and go for round one, but we’re confident this injury won’t impede his availability much further beyond that,” the Saints' footy boss David Misson said.

"One silver lining is that Marcus is very attuned to the best way to rehab this injury, so we’re confident he’ll get to work and be back as soon as he can."

Despite exiting concussion protocols after copping an elbow to the face during training on February 12, Hunter Clark remains on the Saints' injury list after straining his calf at training on Monday.

The 24-year-old, who missed five games last season with a knee injury, is expected to miss four to six weeks as he rehabilitates the strain.

"Hunter had graduated concussion protocols and was reintegrating back into full-contact training," Misson said.

"Unfortunately, in a relatively innocuous moment of training, he strained his calf in a way we don’t often see.

"While we’ll have to monitor his progress, an injury like this could require a rehab period of four to six weeks."

It's the latest incident in a torrid injury run for Clark, who was restricted to just eight games in 2022 and 13 in 2021 through assorted facial fractures and shoulder surgeries.

Despite leaving the field early during Friday's match sim, Liam Henry and Josh Battle have been cleared of any injury and are available for selection in Sunday's AAMI Community Series match against North Melbourne.