ST KILDA young gun Nick Coffield has suffered a torn ACL tear after scans confirmed the club's fears on Saturday afternoon.

The 22-year-old suffered the injury to his right knee during a match simulation session at MARS Stadium on Friday morning.

Coffield went down after planting his foot and immediately appeared in distress, with play brought to a standstill for five minutes while the young defender was helped off the ground in Ballarat.

The Saints are currently working through when Coffield will undergo a knee reconstruction, but he is expected to have surgery in the next week or two. 

Saints young gun Nick Coffield in action at training on January 19, 2022. Picture: AFL Photos

"Nick had been doing everything right this pre-season and we were really looking forward to seeing what he could achieve this year," chief operating officer Simon Lethlean said.

"This is a big blow to Nick, but we know he’ll be doing everything he can to get back out there as soon as possible.

"While this is a significant setback, Nick has the full support of the entire club as he attacks his rehabilitation."

It is a devastating blow for the 2017 No.8 pick who had been one of St Kilda's most impressive performers on the track this pre-season.

After finishing fifth in the 2020 Trevor Barker Award following a breakout season, Coffield struggled for consistency last year but many inside RSEA Park were thrilled with his dedication over the off-season and pre-season. 

Coffield and Max King invested in a private running coach over the break and were two of many young players who had made significant progress under the watch of new high performance boss Nick Walsh.

The level of investment Coffield had put into his preparation in recent months made the incident on Friday even more difficult to come to terms with for Brett Ratten, Lethlean and senior figures in the football department.

Just when the Saints looked like putting a nightmare injury run behind them – Jade Gresham, Jarryn Geary and Dan Hannebery played a combined total of eight games in 2021 and are all set to play in the pre-season practice matches ahead of potential round one returns – St Kilda is set to be without one of its brightest young talents for the next 12 months.

Saints young gun Nick Coffield in action at training on January 19, 2022. Picture: AFL Photos

Ratten had been bullish about Coffield as recently as this week but the out-of-contract coach will get small defender Ben Paton back from a broken leg, as well as former skipper Geary, who managed only three games in 2021 due to a fractured leg and shoulder reconstruction.

Mature-age recruit Tom Highmore played 13 games in St Kilda’s defence last year after being plucked out of the SANFL at the end of 2020 and looks set to become a more permanent option. While Josh Battle has also been used down back in the past year and Jimmy Webster overcame a horrid injury run to play 20 games in 2021 after not playing once the previous season.

The Saints have two list spots available ahead of the pre-season supplemental selection deadline period and weren’t expected to use more than one spot before Coffield went down.

Woodville-West Torrens star Jack Hayes is set to earn one of those spots after training with the club since December, but with another spot becoming available – and the unknown of COVID-19 in 2022 – St Kilda may explore adding another player before the deadline on March 9.

Coffield has played 52 games since he was selected with the pick after Hunter Clark in November, 2017.