Cahill – who turned 38 in December – first joined the Championship side as a teenager 20 years ago.

He scored 57 goals in 251 appearances for the East London club  where he played alongside current Millwall nmanager Neil Harris, and is still hailed as an all-time club legend.

He was with the club for seven years after joining as a youth from Sydney United following two years at Sydney Olympic.

"It's an amazing feeling," Cahill said today. "To finally come home and join Neil Harris, David Livermore and all the lads will be really special.

"I can't wait to greet the fans, meet my new team-mates – it's one of those things where it's meant to be."

He added: "The romance of the story is definitely not lost on me. I've always said that if I came back to England, I'd come home.

"Millwall is where I learnt my trade and it was the most important learning period of my life – my apprenticeship in understanding football.

"To come home where it all started, it's emotional, but it's happy emotions, because you wish for it to happen, you want it to happen, but when it finally comes to fruition, it's the perfect move."

He left the Den for Everton in a $2.5m transfer deal in 2004 where he put in an another myth-mkaing stint, scoring 56 goals in 226 games.

His return to Millwall will allow him to play out the season and put himself back in contention for a spot in Socceroos coach Bert van Marwijk's squad to go to the World Cup in June.

Cahill exited Melbourne City in December after struggling for game time under new coach Warren Joyce despite averaging a goal every other game the previous season.

But he left it deep into the transfer window before agreeing terms with Millwall, with few other clubs apparently willing to take a gamble on the veteran striker.

He will now have six weeks to prove himself in the Championship before van Marwijk selects his first Australia side for the upcoming friendly against Norway on March 24.

Millwall boss Harris hailed the capture of the club legend, which is being touted on Twitter with the hashtag #TheReturn.

"I'm naturally really pleased," Harris told the club website. "First and foremost, Tim comes with a wealth of experience. Not just in the footballing world, but for this football club. It might have been just over 13 years since he left, but this place doesn't change.

"There's still the same morals and principles and it's a workman-like football club. Tim has been around the world playing, but his attitude, his discipline and his lifestyle hasn't changed one bit. In so many ways, he is still the kid I used to share a dressing room with years ago.

"The players will thrive off the enthusiasm that he brings. When I played with him, I appreciated what he did. Since then, I've followed his career and admired what he has done and I know full well what he can bring to my dressing room.

"He is a different player to what he was years ago - he plays a little higher up the park now. At 38, he is in terrific shape. To start with, we are thinking about impact - someone to come off of the bench and give us that little lift, someone to lift the crowd and someone to pass on that knowledge when in front or behind."

Harris said Cahill was determined the make the move, despite reported late interest from both QPR and Nottingham Forest.

He added: "I'm really pleased. It's taken us January to get there, but the reason we're here is because of Tim's committment to come. He had lots of offers, lots of places around the world that he could've gone to, but he chose Millwall. I'm delighted to be bringing him into the squad."

"What he will bring into the dressing room is standards and leadership. He lives his life in the right manner. He'll be the first in and the last to leave. He'll add to the leadership we already have at the club in Steve Morison and Tony Craig. Because of the shape he is in, he'll demand everyone is at that level.

"At 3pm on a Saturday afternoon we'll have a benefit, but from 9-5 every day of the week, he'll have an input."