He started off as a small fish in a massive AFL pool, but Colin O’Riordan has overcome early doubts and fears to become Sydney’s latest Irish success story.

After just 13 senior games, the 23-year-old defender has signed a two-year extension taking him through until the end of the 2021 AFL season.

He made his senior debut last year and is having a breakout season, playing the last nine games and emerging as a developing talent in a difficult season for Sydney.

“This club gave me an unbelievable opportunity and I just want to repay their faith, and that’s really what drives me,” former Gaelic footballer O’Riordan said.

“You always have a bit to prove and I don’t think I can ever really settle.

“I think you always have to be a bit on the edge and that’s what I try to do.”

O’Riordan signed an international rookie contract with the Swans in 2015.

“It was a mixture of fear and excitement,” he said.

‘”You come here and you are the smallest fish in a massive pond and that’s something that takes a while to get used to, you have to learn a brand new game.

“‘At times I had doubts.

“When you’re playing bad footy and you’re not yourself it can be a bit frustrating and you just don’t know if you’ll ever pick up the game but you just have to believe in yourself.”

O’Riordan is following in the footsteps of compatriot Tadhg Kennelly, a member of Sydney’s 2005 premiership-winning side, who is now an assistant coach and oversees the defence.

‘He’s been through the whole process and to have him just to ask for advice and to share his thoughts on the journey is unbelievable,” O’Riordan said.

He said there was a lot of talent back home who had the potential to make the AFL but the but the main challenge was getting the mental side right.