Martin, who plays at centre or wing, has an outstanding rugby league record that stretches 14 seasons and 253 first grade appearances including two spells with London Broncos where he was a fan favourite.
A try scoring and goal kicking machine, the 31-year old has scored 79 tries and kicked 320 goals and a drop goal in his illustrious career with the Warriors, London, Melbourne Storm and Wakefield Trinity Wildcats.
With Melbourne, Martin scored a try in their 1999 Grand Final win against St George Illawarra, the 20-18 win being played in front of a rugby world record crowd of 107,999.
Martin, who has already arrived in Wales, is looking forward to his new challenge.
“I’m really excited about getting in there at the Crusaders as a club that’s still young,” he said. “I’ve been in similar clubs at London Broncos and Melbourne Storm who aren’t in the so-called rugby league heartlands and were trying to break through in their respective areas. To do the same in Wales, we need to make it a real family environment, do the right things and play well on the field. I feel that I and all the other new players are lucky to get this opportunity and I really want to help to make it all work in Wales.”
Witt, who turns 26 on Friday, will be arriving in Wrexham next Monday after securing a work permit and will join the squad as they prepare for their opening Super League game at home to Leeds Rhinos on Friday 29 January.
He has just finished a short spell with the Otago rugby union club in New Zealand but before that had spent six successful years in the NRL scoring 23 tries and kicking 258 goals and three drop goals. He spent two seasons with each of his three clubs, Parramatta Eagles in 2003-04, Manly Sea Eagles in 2005-06 and New Zealand Warriors in 2007-08.
Toowoomba-born, Witt was also a champion junior boxer before turning to rugby league. Despite being born and brought up in Queensland, he turned out for New South Wales under 19s while at Parramatta and for NSW Residents while at Manly.
Witt can play at either of the half-back positions (scrum half or stand-off).
Tickets for Crusaders v Leeds Rhinos on Friday 29 January (kick-off 8pm), priced from £7 for juniors, £10 for concessions and £15 for adults, are available to buy online by going to www.crusadersrfl.com/tickets.htm or by calling 01978 262129.