“He's improved a lot since he came back from Germany and the Bundesliga,” said Arnold today.

“I had doubts about him playing on the left side of a back four but he's shown in round one against Sydney in the A-League, he can play there. He's adaptable.

“I've thought of him as a wingback in the past, but he's proved he can play as a defensive left-sided player too. In season one he scored a lot of goals and now he's matured a lot.”

Arnold stressed the importance of finding a natural left-sided player to replace Scott Chipperfield for the future of the national team, following the retirements of Tony Vidmar and Stan Lazaridis.

“I'm looking at the big picture," he said. "Some people don't look at the big picture. We need left sided players, we've had so many retirements.

"And right now, Chippers is 31.”

The rise of Heffernan, 27, from state league player to Socceroo, has been stunning.

Just two years ago, he was playing in the NSW state league with Sydney United.

Lawrie McKinna picked him up for the Mariners' first A-League season where Heffernan starred as a free-scoring left back.

After a tough season in Germany at Nuremburg last season - where he struggled to break into the first team - the player returned to Central Coast and has impressed many observers.

In last weekend's game against Sydney, he cut an imposing figure in defence with a series of tough challenges, including a controversial one on Mark Milligan.