Young Sydney Swans forward Tom McCartin was in “a bit of shock” when coach John Longmire knocked on the door of his home and told him he’d be making his AFL debut.

Going on to fill the giant boots of 2012 premiership forward Sam Reid in 15 games in his first season as a Swan made for an even bigger surprise.

But Geelong Falcons product McCartin, the youngest player in the AFL in season 2018, hopes to reap the rewards of being thrown into the deep end from the get-go.

“I definitely wasn’t expecting to play that many games,” McCartin told Swans Media.

“I wasn’t even expecting to play one AFL game, let alone 15. But it was such a great experience and looking back I’ve learnt so much from playing that many games in my first year. I’m so glad I got the opportunity to play those games and I’m looking forward to taking what I learnt in 2018 into 2019. Hopefully I’ll be able to put a few more games together and play some good footy.

“It was a bit of a shock when John came to my house and told me I’d be making my debut. I wasn’t expecting it at all. Looking back it was a bit of a whirlwind, that whole three or four days, from when John told me to when I played.

“It was all such a good experience and wish I could do it all again.”

A host of key defenders went head to head with McCartin and fellow tall forward Lance Franklin in 2018.

West Coast threw up Shannon Hurn and Jeremy McGovern, Richmond presented Alex Rance and Essendon unleashed Michael Hurley, all of whom are All Australian defenders.

But Longmire continually showered in praise McCartin’s impact at AFL level in 2018, underscoring his ability to launch for marks and get the ball to ground for Tom Papley, Ben Ronke and the rest of Sydney’s small forwards.

McCartin also stood tall in a number of crucial moments, with his miraculous match-winning goal against Collingwood at the SCG in Round 20 topping the highlights reel.

The 18-year-old said going toe to toe with many of the competition’s best key defenders had made for a rewarding challenge.

“The amount of stuff I learnt in 2018 from playing against some of the best defenders in the comp was huge,” McCartin said.

“You want to be testing yourself against the best defenders in the comp because that’s what gives you the best gage of how you’re tracking, so 2018 was really important for me in that way.

“Hopefully I can take a few of those things I’ve learnt into 2019. I’m very grateful for the opportunity. I was definitely tested in my first year and I expect that to help me in a number of ways going forward. That’s the quickest way to learn and it’ll definitely help me with my confidence and the physical side of the game.”

The Swans returned to the club for an opening block of pre-season training ahead of Christmas across November and December, and McCartin says he’s putting in the hard yards ahead of his 2019 campaign.

“It was good to get back into it,” McCartin said.

“I tried to do everything I could over the off-season to prepare myself for the pre-season. I got through uninjured and when we get back from the Christmas break I’ll put in some more hard work and go from there.”