Sir Alex Ferguson is confident Manchester United will win any legal fight with Gabriel Heinze over his proposed move to Liverpool.

It has now been confirmed that Heinze has employed a team of lawyers to investigate whether United are right to block a transfer to Anfield, even though Reds boss Rafael Benitez has met the £6.8 million asking price for the 29-year-old.

The shock move effectively renders his Old Trafford future untenable.

Yet United are sticking to their guns in refusing to let Heinze become the first player to switch between the bitter North West rivals since Phil Chisnall moved to Merseyside in 1964. And, having ordered Heinze to be back in training on August 6, Ferguson has made it clear he expects the Argentina international to meet the deadline.

"We are aware Gaby is taking legal advice," Ferguson said. "That is good. I hope it is good advice because we are confident of our position. He is due back in training on August 6, which gives him three clear weeks' rest after the Copa America. And we expect him back in training a week on Monday."

The deadline effectively gives Heinze's lawyers a week to find out if the former Paris St Germain defender has a case, which revolves around whether a letter signed by chief executive David Gill, confirming the figure United would be prepared to sell Heinze for, overrides the player's contract which still has two years to run.

Gill claims he informed Heinze's agent verbally, prior to Liverpool revealing their interest, that United would not be prepared to sell him to any of their three major domestic rivals; a discussion which is thought was recorded and could therefore, in theory, be used as part of any defence the Red Devils may wish to put forward in court.

Heinze has been the subject of interest from overseas, with Real Madrid and Inter Milan among the clubs to express an interest. But, the huge Spanish-speaking influence at Liverpool, plus an opportunity to remain in the North West, appears to have an irresistible lure for the player.

After pinning much of the blame for the present situation on Heinze's agents, Ferguson must now accept the defender is also a prime mover. After hailing the 2004 Olympic champion a hero, the tide of supporter goodwill is almost certain to turn against Heinze. Even if he remains at Old Trafford, it is difficult to see him being involved when the champions open the defence of their Premier League crown against Reading on August 12.