St Kilda co-captain Jack Sinclair has been ruled out of his side's clash with the Western Bulldogs, succumbing to a calf complaint in the first term.

Alone in defensive 50, Sinclair was running backwards, and when he attempted to shift gears and head towards the centre square, he was seen clutching at the muscle and in some discomfort. The non-contact nature of the injury is sure to instil fear in St Kilda fans.

At the first change, the 31-year-old was sighted sporting a moon boot on the affected extremity, with scans in the coming days sure to reveal the nature of the injury, and a projected recovery timeline for the quarterbacking distributor.

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MELBOURNE, AUSTRALIA - AUGUST 19: Jack Sinclair of the Saints in action during the 2023 AFL Round 23 match between the St Kilda Saints and the Geelong Cats at Marvel Stadium on August 19, 2023, in Melbourne, Australia. (Photo by Dylan Burns/AFL Photos via Getty Images)

The dual All-Australian has suffered a grumbly calf in the past, missing his side's Round 1 clash in 2024 with a similar complaint.

Elsewhere, high-profile acquisition Tom de Koning has been ruled out in the third term with a rib complaint. The ruckman took a knee to the ribcage from the athletic Buku Khamis in a marking contest, and succumbed to the pain, after initially telling broadcaster Fox Footy that he would continue.

After an even opening to proceedings, the Bulldogs have pulled away in the third term, and currently lead Ross Lyon's Saints by three goals, five minutes into the third stanza.

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