MADRID, Spain (Reuters) -- Spanish champion Real Madrid has agreed to sign Argentina defender Gabriel Heinze from Manchester United on a four-year deal.

"Real Madrid and Manchester United have reached an agreement for the transfer of Gabriel Heinze," the Primera Liga club said on their Web site on Wednesday. "The player will join up with his new team immediately."

The transfer fee was undisclosed but Spanish media reported Real would pay about $16.2 million for the 29-year-old.

English champion United confirmed on its Web site that Heinze had agreed to join Real.

Heinze, who made 83 appearances for United, had made it clear he wanted to leave Old Trafford but his attempt to force a move to Liverpool failed when a Premier League arbitration panel refused his request.

The defender is the seventh new player to join since Real sacked coach Fabio Capello after winning the title.

Five of the new signings can play in defensive positions, including center backs Christoph Metzelder, Pepe, left-sided midfielder/defender Royston Drenthe and goalkeeper Jerzy Dudek.

Heinze will compete with Drenthe, Marcelo and Miguel Torres for the left back berth vacated when Roberto Carlos left at the end of the season.

The Argentine, who can also play in central defense, joined United from Paris St. Germain for $13.7 million in 2004 following spells with Sporting Lisbon, Spain's Valladolid and Newell's Old Boys.

Renowned for his combative attitude, he damaged knee ligaments in a Champions League match against Villarreal in September 2005 and missed the rest of the season, although he recovered in time to make the Argentina squad for last year's World Cup.

More recently he has found his first-team place threatened by French fullback Patrice Evra, who signed for United in January 2006.

At the end of last season Heinze claimed he had a letter from United giving him permission to move to another club for $13.5 million, a fee Liverpool agreed to pay.

But United refused to permit him to join its rival and the Premier League panel ruled the letter did not give the go-ahead for his move.

Heinze was a member of the Argentina team that lost to Brazil in the Copa America final in July.

Copyright 2007 Reuters Limited. All rights reserved.