The players (clockwise from top left): Quinn, Van Dijk, Mapp, Hannay, Dalle Cort and Duggan
Crusaders have been fined £5,000 after failing to carry out checks on one of their six players who were deported last year.
The UK Border Agency (UKBA) found visas used to bring the Australians to the then Bridgend-based club were invalid.
Captain Jace van Dijk, top try-scorer Tony Duggan and star-player Damien Quinn were among the banished players.
The Crusaders provided evidence that checks were made on five of the six players before employing them.
But it is not known which player they did not provide evidence for.
"Businesses have a legal responsibility to carry out the correct pre-employment checks on their workers and those who do not can be fined," said Jane Farleigh, regional director of the UKBA in Wales and the south-west.
"As this case shows, we will not turn a blind eye to foreign nationals working in the UK without permission.
"The players involved have been required to leave the country and the employer has been fined for failing to carry out all the checks required by law."
The six players are Darren Mapp, Mark Dalle Cort, Josh Hannay, van Dijk, Duggan and Quinn, who have been banned from the UK for 10 years.
Discrepancies were found in the visa applications of the six players in seasons prior to 2009.
The Crusaders have endured a difficult first Super League season last year, winning only three games.
Off the field, they and their investors have also faced "difficult" financial conditions because of the credit crunch.
Since then, the club has been taken over by former Wrexham chairman Geoff Moss and relocated to Wrexham.
Brian Noble has replaced John Dixon as coach and the Crusaders have won two of their opening four Super League games this season.