Manchester United boss Sir Alex Ferguson has revealed his fury at Tottenham Hotspur signing former Reds defender Ezekiel Fryers and accused them of "blatant manipulation".
The 20-year-old was out of contract at United last summer and looked set to join Spurs, but the two sides failed to agree a compensation amount, United reportedly wanting £6m for the England youth international.
Fryers subsequently joined Standard Liege on a two-year deal and then made the move to White Hart Lane as soon as the January transfer window opened, in a reported £3m deal.
While United are yet to make a formal complaint to the Premier League, Ferguson has been left reeling and called for the transfer to be blocked until it has been fully examined.
Speaking to MUTV, Ferguson said: "To me, I think it's a blatant manipulation of the rules.
"Tottenham did nothing wrong as he went to Standard Liege. They tried to buy him off us and we'd been looking for a certain figure. They wouldn't pay it but asked if they could take him down there on trial and, at that time, he was out of contract in June anyway.
"So he went down on trial and he went to Portugal with them. They then said they weren't prepared to pay the money and, all of a sudden, he signed for Standard Liege.
"We knew immediately and suspected that he would return to Tottenham in January and that's happened. It's a [Spurs chairman] Daniel Levy deal. You know, it's his fingerprints all over it. It's the kind of thing we expected he was going to do.
"The league should look into it. They should stop the registration until they examine it. There will be a trail. Either mobile phones or something. It is obvious to me."
Tottenham have defended the deal they agreed with Fryers, a club spokesman said: "Zeki Fryers was out of contract in the summer. We had looked in to the possibility of signing the player but were unable to agree a deal on the terms Manchester United were asking.
"Zeki chose to go to Standard Liege, who paid compensation to Manchester United. Zeki enjoyed his time at Standard. However, when Standard sacked their manager in November Zeki wasn't part of the new manager's plans, which he accepts and understands happens in football.
"Unfortunately, a combination of this, and the fact that he had become homesick meant he wanted to return to England and his representatives made contact with clubs in England. This afforded us a second opportunity to sign the player and as per FIFA's solidarity contribution mechanism, Manchester United will receive five per cent of the transfer fee we have paid."