London - Manchester United have signed Athletic Bilbao midfielder Ander Herrera on a four-year contract, subject to the receipt of an international transfer certificate, the English Premier League giants announced Thursday.
United said the move had neared completion after the 24-year-old Herrera triggered the buy-out clause in his Bilbao contract on Tuesday.
The 24-year-old, who joined Bilbao from Real Zaragoza in 2011, has been capped by Spain at Under-20, Under-21 and Under-23 level.
"Signing for Manchester United is a dream come true," Herrera told United's website.
"I have played at Old Trafford for Athletic Club in the UEFA Europa League and it was one of the highlights of my career so far. I have joined United to do all I can to help the team reach the club's objectives.
"Having arrived on Tuesday, I'm excited to now be living in Manchester and I can't wait for my first game in United's famous red shirt."
He added: I will never forget my time with Athletic Club and I'd like to thank the fans and staff for all their support and, above all, wish all my fantastic former team-mates all the best for the future."
United assistant manager Ryan Giggs forecast a bright future at Old Trafford for Herrera.
"Ander is a fantastic young player, with great energy and creativity. We believe him to be one of the brightest young prospects in Spain and I am certain he will be a big hit with the United fans.
"I'm delighted he has made the decision to come to Manchester and play his part in the club's future. I'm looking forward to seeing him in action on our summer tour to America."
United had previously attempted to sign Herrera in August last year only to fail in bizarre circumstances on transfer deadline day.
Reports emerged of three people, believed to be representing United, managing to enter the Spanish league's headquarters for talks about the proposed move and then leaving an hour later, seemingly unable to complete the paperwork required to seal the deal.
It subsequently emerged that United, who dealt directly with Bilbao, knew nothing of the trio's existence.
Negotiations between the clubs then collapsed but, with United having sacked former manager David Moyes and replaced him with Louis van Gaal, Herrera is now on the brink of becoming the Dutchman's first Old Trafford signing, subject to international clearance.
United, who were the reigning Premier League champions, finished a disappointing seventh in the table last season and so missed out on qualification for both the European Champions League and the second-tier Europa League.