Heinze's attempts to join Liverpool were blocked by a Premier League hearing, which sided with United over who they could sell him to once their £6.8 million valuation had been met.

Benitez attacked the Premier League decision, which could leave Heinze's career in limbo until his contract ends, and he has also directed his fury at the Old Trafford hierarchy.

In a newspaper interview, Benitez claimed decisions are being taken which favour Liverpool's old rivals with yesterday's dismissal of Heinze's bid to move to Anfield the latest setback.

Benitez said: "I would like to ask the Premier League a number of questions. How can a player with a signed agreement be treated like this?

"He has a document which is clear, but the Premier League prefers to believe the word of someone else who made a mistake. I know there were accusations made against Liverpool in the hearing which were unbelievable. How can this be allowed?"

Broadening his attack from the Heinze issue, Benitez said: "Then I would like to ask the Premier League why is it that Liverpool always plays the most fixtures away from home in an early kick-off, following an international break?

"We had more than the top clubs last season and we have four already to prepare for this season.

"Then I want to ask the Premier League why it was so difficult for Liverpool to sign Javier Mascherano, when we had to wait a long time for the paperwork, but it was so easy for Carlos Tevez to join Manchester United?"

Mascherano joined Liverpool from West Ham in the January transfer window and the deal took weeks to clear amid the row over third party ownership of players at Upton Park.

The Tevez move to Old Trafford took less time to approve, with the player's representatives paying West Ham £2m to release his registration in time to beat the transfer deadline.

Benitez said: "It's going to be very difficult for us to win the Premier League because the other teams are so strong, but I want our supporters to know that despite the disadvantages we have, we will fight all the way.

"We will fight to cope with our more difficult kick-off times and all the other decisions which are going against us."