Tadhg Kennelly has hailed fellow Kerryman Mark O'Connor's instant adaptation to Aussie Rules ahead of the 20-year-old's AFL debut this weekend.

Two-time minor All-Ireland winner O'Connor, who only moved to Australia on a two-year international rookie contract last October, has been drafted into the Geelong senior squad to face Essendon after only four games in the second-tier Victorian Football League.

O'Connor has been called up due to a serious hamstring injury to Brandan Parfitt and will take his place in the team alongside Laois native Zach Tuohy.

The fact that the Dingle native has made the step-up far quicker than most Gaelic football converts is no surprise to Kennelly, the only man to win a Championship in both codes.

Kennelly says that he realised O'Connor had real promise after learning he made his minor debut for Kerry at just 15.

"When you see that, straightaway you say ‘hang on a second - he must be something special’," Kennelly told foxfooty.com.au

"He’s one of those players with fantastic composure and decision-making under pressure.

"Everything around him looks like it’s going in slow motion. He’s very calm and that’s what separated him in the under 18s in Ireland - every time there was a big moment, he was the one that took over the game.

"He’s got a long way to go, but he’s making blokes like us look very poor. We struggled to get a game and now it’s Round 8 and he’s straight in.

"It’s an incredible achievement and an incredible story."

Former Sydney Swan Kennelly, who now works as a coach, believes O'Connor has the physical and mental attributes needed to make it in the professional game Down Under.

"He’s able to identify what’s needed right there and then," said Kennelly.

"It’s hard to quantify it in terms of numbers, but he can run - he’s got really good endurance - and he’s got very good marking ability.

"That sort of stuff is very hard to identify from a recruiting perspective, but when you’re actually watching him play live you can clearly see it. He’s got a great temperament to be a professional footballer.

"He’s a relaxed boy and a real thinker. He won’t blab his mouth off, he’ll sit down and listen to a conversation and really think about it.

"You’d think he’s quiet, but he’s just taking things in, which is really good for a young player because there’s a lot to take in at his age."