Adding more confusion to the baffling departure of Sonny Bill Williams is the fact the legal fraternity is at odds about the prospect of action against the runaway.

Two sports law experts yesterday gave conflicting opinions about the chances of the Bulldogs successfully preventing Williams from playing rugby union in France.

Tony O'Reilly, a director of the Australia and New Zealand Sports Law Association who has previously represented the NRL, believes the Bulldogs would be justified in attempting to gain a court injunction to stop Williams from playing rugby. "The simple answer is the courts don't look very kindly on people who blatantly dishonour their legal obligations," said O'Reilly, who has previously represented former Olympic swimmer Ian Thorpe in defamation proceedings and specialises in sports law.

"You can't force him to play for the Bulldogs but you can stop him from playing for anyone else. I expect the Bulldogs will pursue every avenue available."

Bulldogs chief executive Todd Greenberg met NRL boss David Gallop yesterday and was told the league would give the club its full support.

"It'll be a test case for the club, the game, and potentially other sports," Greenberg said. "We'll certainly be doing everything in our power to ensure our contract is honoured."

Asked if he was prepared to make Williams sit out the remainder of his contract, Greenberg said: "All of those things are on the table. We're talking about the commitment of a contract. If he's not playing with the Bulldogs, he won't be playing football, full stop."

Bulldogs coach Steve Folkes echoed those sentiments, saying: "If [Williams] is successful, it's pretty much open slather for anyone."

But there were fears yesterday that the Bulldogs, and the NRL, would be powerless to prevent Williams playing rugby union in France.

"Without having seen the contract, and without pre-empting what the court might do, I'd expect it would be very tough to obtain an injunction, especially given that Williams is in France and he's playing in a different country and a different code," barrister Paul Hayes, a sports law expert, said.

The Bulldogs will also explore suing Williams for damages amid concerns over the ramifications for the club's sponsors and gate takings. "On the back of Sonny's commitment to the club, the club has in turn made several commitments to players, sponsors, supporters and members," Greenberg said. "The ramifications of his decision to leave the country are fairly significant."