That soon changed, because the doctor had some concerning news. Milera, who had his ECG done while part of the South Australian under-18 program, as a standard part of the squad's medical screening, was told he was born and had been living with a condition called Wolff-Parkinson-White syndrome, which had created a second electrical pathway through his heart. If undetected, his heartbeat might have increased rapidly one day, out of nowhere. "If they did nothing," he said, "I might have just fallen down one day on the field, without any warning.

The first thing Milera's parents wanted to know was whether he would be all right. The first question he asked his specialist was whether the condition would prevent him from playing football, or limit him in any way. He was told he needed to have it fixed – that there was no choice – but that once he did, he would have no further problems.

"It didn't worry me too much after that," Milera said. "It was stressful to think about, because the specialist had this little heart and he showed it to me and explained what he had to do. It sounded pretty complicated to me, with that he was saying about how he had to do this and do that. But after that, all I wanted was to have it done."

Once it was, other things became frustrating. Milera had become a regular part of the Central Districts team by the time he was diagnosed: quick, creative and clever, he was getting better by the week, inching further and further up AFL club draft boards. He went into hospital on the Monday before the team played in an elimination final, set straight as soon as he asked whether he would still be able to play on the weekend.

"I thought I might be able to sneak back in," he said, "but the doctor told me straight away that I had to rest. I still went down and watched them play and I was sitting there all day just hoping they would win the game."

They did, and Milera was back in the side the next week, kicking three goals in a five-point win over Port Adelaide that pushed the Bulldogs into a preliminary final. While the two-hour catheter ablation "wasn't all that much fun", he had been able to go home on the same night and jog a few laps of the oval by the end of that week, reassured by his coach that if the team won through he would be back with them the next week.

"The coach was really good to me," said Milera, who had no nerves at all about getting back out onto the ground. "My form leading up to the finals gave me a lot of confidence and made me feel like I was part of the team. And it was my first final for the team and my first time playing on Adelaide Oval. I couldn't wait to play, I was keen to get out there and try to get a few kicks. It was only afterwards that I thought, how lucky am I that we had to have the test done. You wouldn't want to just collapse on an oval out of nowhere."

It means there is just one thing on his mind now. Or, rather, two: finishing school off in the next few weeks and then waiting to see which club drafts him. Milera feels as though the things he learnt playing senior footy this year – how to get through a pre-season, how to make snappier decisions, how to get around bigger bodies – have made him a better, more prepared player.

He hopes the AFL clubs think the same things."It's really exciting but there's also a lot of unknowns at the moment, wondering about what they all think and what they see in you," he said. "You don't know if you're going to get picked or where you're going to get picked up or where you might be next year. I just have to wait now, to find out whether they want me."