There was widespread concern on Sunday about former No. 1 draft pick McCartin, who was concussed during his side's loss to Gold Coast on Saturday. It was the 20-year-old's third concussion in less than three months, and his fifth since 2014.

Saints doctors are set to assess the emerging spearhead early this week, while the AFL Players' Association are likely to contact the youngster, while trusting St Kilda to act in his best interests.

Blease is one of several recent players whose careers have ended prematurely because of concussion. The midfielder – who spent six seasons with the Demons and one at Geelong – called time on his career last year after struggling to overcome the symptoms of a concussion sustained while playing in the VFL.

Concussions have been treated with increasing conservatism in the AFL, with players such as Hawthorn's Jack Fitzpatrick, Saint Billy Longer, North Melbourne's Lachie Hansen and Demons Angus Brayshaw and Heritier Lumumba all enduring prolonged stints on the sidelines following concussions this year. Brayshaw missed four weeks of football after he suffered two concussions in a fortnight while playing in the VFL earlier in the season.

Blease thought a young player like McCartin would be keen to return soon, but he urged caution, even it meant McCartin missing much if not all of the balance of the season.

The former Demon and Cat cited the example of Brayshaw – taken two picks after McCartin in the 2014 draft – as an example of how to deal with repeat concussions in a promising youngster.

"It's a difficult one, because you want to be playing as much as you possibly can at that age," Blease said.

"The stigma has certainly changed but there still would be some players that maybe would be pushing the envelope to get back because they're at different stages of their careers.

"I think Melbourne handled their situation with Angus Brayshaw as well as anyone and [with] Heritier Lumumba [as well]. There's no pressure there, it's 'get back when you're right to play'. That's the right way to go about it."

Blease said clubs had improved markedly in their management of concussions. "Now a days with what we know now compared to five, 10 years ago, clubs are taking this seriously," he said.

"You've only got to look at the last two or three years, there's probably been six or seven players retire on the back of concussion.

"I think clubs are realising that yes football is such an important thing for everyone at this present time, but there is a life to be lived when you finish up playing football."

McCartin's injury against the Suns follows concussions against Collingwood in round three and Adelaide in round 11. While McCartin played the week after the Magpies game, he missed two weeks after the Crows encounter. He also missed a game following a concussion while playing for the Saints' VFL affiliate Sandringham last year, as well as being concussed during the 2014 under-18 national championships.

The string of blows to his head are an added challenge for McCartin, who was diagnosed as a type-one diabetic when he was nine, and needs to monitor his insulin levels during games.

He needn't look far for guidance on managing concussions, with fellow tall and Saints captain Nick Riewoldt suffering a handful of concussions during his career, including an incident in May last year and April this year.

Saturday's defeat effectively ended any faint hopes held by the Saints of making the finals. Alan Richardson's side is three games and heavy percentage outside the top eight, and faces Essendon at Etihad Stadium next Sunday.