Few AFL players have endured as tough a journey to the 100-game milestone as St Kilda star Justin Koschitzke who will finally bring up his century of games on Friday night against the Western Bulldogs at Telstra Dome.

It has taken the 25-year-old just over seven seasons to bring up the ton because of numerous serious injuries and to put into context just what a struggle it has been for the talented key position player, consider the amount of AFL games already played by some of the other stars who were taken in the same draft as Koschitzke back in 2000.

Koschitzke was taken at pick two in that draft behind teammate Nick Riewoldt, who has already chalked up 136 games while the Eagles' champion midfielder Daniel Kerr - taken at pick 18 in the same draft - has played 146 games.

However St Kilda coach Ross Lyon said he never doubted Koschitzke, one of the most valuable key position players in the game, would reach 100 games despite the big forward at one stage playing just 20 games in two seasons during 2005 and 2006.

"He was always going to get to 100 because he has got exceptional talent and he is exceptionally dedicated," Lyon said of Koschitzke ahead of Friday's clash against the Bulldogs.

"You are always going to have battles along the way whatever you do whether it's playing footy or whatever else you are doing."

This week's clash against the Bulldogs also marks the 100th game of Xavier Clarke, who himself has battled injury problems over the years but has taken one less year than Koschitzke to reach the century mark after being picked up by the Saints at pick five in the 2001 national draft.

"It's great to see early draft picks come through and play really good football for your club," Lyon said of Koschitzke and Clarke.

Koschitzke began his career on a high in 2001 when he played 20 games in his debut season and took home the AFL's prestigious Rising Star Award for the best young player of that season.

But his injury problems began the following year when a back injury limited him to just four games.

The next two years were productive, yielding 17 games in each of 2003 and 2004, but in 2005 quad and hamstring injuries limited him to just 13 games and crucially he missed the finals series that year.

And many Saints' fans still believe that Koschitzke's absence from the finals in 2005 cost the club a premiership after it was overrun in a home preliminary final by eventual premiers Sydney, particularly given Koschitzke's form during the middle of that season when fully fit.

In a devastating five game spell between rounds 14 and 18, Koschitzke - playing both as a ruckman and as a key forward - produced the amazing statistics of 94 possessions, 48 marks, 53 hit-outs, 19 goals and 11 Brownlow votes and if he had been fit and in that kind of form come September, many people believe the Saints wouldn't still be waiting for their first flag since 1966.