Before he arrived in Australia almost two weeks ago to trial at four clubs and in front of more at the NAB AFL Draft Combine, the 18-year-old Irishman was in demand. But not until being here, and seeing his opportunities first-hand, was McKenna certain he wanted to stay.
"I always wanted to do it but I wasn't sure until I got over here and started seeing clubs," he told AFL.com.au. "Now I've made a decision I want to come, so hopefully I get a contract offer and will be here in November for the start of a pre-season."
McKenna's talents were first spotted at a talent combine in Ireland last December, when an Essendon scout took in proceedings. More recruiters became interested in April, when McKenna played for the European Legion against the travelling AIS-AFL Academy squad in London.
In his first game of football, the quick and agile 182cm prospect kicked four goals and was almost best afield, sparking more interviews and attention from the travelling clubs on the tour.
Since then the teenager has finished his season with Tyrone in the Gaelic league, taken a hold of a couple of footballs and kicked them around his house and local 'pitch' as much as he could to get his kicking and touch up to scratch. "For me it's the next step up from Gaelic. Here, it's a job," McKenna said from Etihad Stadium at the four-day combine.
After he touched down in Australia he spent three days training with West Coast in Perth before flying to Melbourne and going out to the Bombers' new facility at Tullamarine. "That big hangar is amazing," he said. He went back to the club on Friday to meet some officials, having visited the Western Bulldogs and Geelong for interviews in between.
Geelong, he thinks, aren't too interested, having recently signed fellow Irishman Padraig Lucey as a category B international rookie, but on Sunday he checked out Collingwood's facilities and the following day met the Magpies' American recruit Mason Cox.
All of it has been different, but he feels he has a better chance to make a more informed decision now, whichever way it goes.
"There's no real rush on it to sign anything, I might go home and talk to my parents and sort everything out but if something opens up this week it might happen, I'm not sure yet. I just have to wait and see," he said.
"I definitely want it. I've put everything else aside for it. I was meant to go to university this year, but I've put that aside and put all my focus on this, so hopefully it works out and I play for at least two years and see how it goes after that."
He has spoken recently to retired Magpie Marty Clarke about the challenges of transitioning to a new sport, but isn't daunted by what lies ahead.
"From the first time Tadhg Kennelly (the AFL's international talent coordinator) called and asked me to come to the combine, everything's come second," McKenna said.
"I wanted to play it and I've been working towards that. I've got no worries at the moment, I just want to get to a club and get started."