POPULAR St Kilda forward Justin Koschitzke has suffered a setback after sustaining a calf injury at training this week.

The 30-year-old, who has played 199 AFL games, is expected to be on the sidelines for a month but is still a chance to reach 200 games.

Head Coach Scott Watters said, "I know all Saints fans would love to see him get there. In order to give himself every opportunity Kosi must now turn all his energy focus and towards his recovery and fight to get himself back in the frame to be selected.

Koschitzke has played four games in St Kilda colours this year and has been mentoring the Saints younger players at Sandringham, St Kilda’s VFL affiliate.