* Midfielder was vital part of Champions League-winning campaign
* Played all three matches for Croatia at World Cup (Adds details)
Aug 20 (Reuters) - Real Madrid's Croatian midfielder Luka Modric will remain at the European Champions for the next four years after signing a new contract, the La Liga giants announced on Wednesday.
"Real Madrid C. F. announces the extension Luka Modric's contract, linking him to the club for the next four seasons," the club said on its website (www.realmadrid.com).
Modric, 28, has made 67 league appearances since joining Madrid from Tottenham Hotspur in 2012.
He struggled in his first season under then-manager Jose Mourinho, having been asked to play in a deeper midfield role.
The former Dinamo Zagreb star came into his own in his second term, playing a key role in his side's run to their 10th Champions League triumph earlier this year, having also won the Spanish Cup, Spanish Super Cup and European Super Cup in his time in the capital.
He played all three matches as Croatia failed to progress from their group at the World Cup finals in Brazil. (Reporting by Josh Reich; Editing by John O'Brien)