Official: Manchester United sign Sergio Romero

The Argentina international goalkeeper has signed a three-year contract, with the option of a fourth season, after leaving Sampdoria earlier this summer

Manchester United have completed the signing of Argentine goalkeeper Sergio Romero.

The 28-year-old joins United on a free transfer after leaving Sampdoria earlier this summer and has signed a three-year contract with the option of a fourth season.

"I am absolutely delighted to join Manchester United," Romero told the club's official website.

"To play for the biggest club in the world is a dream come true for me. Louis van Gaal is a fantastic manager and I cannot wait to get started on this new and exciting challenge in my career.”

Romero has previously played under Van Gaal at AZ Alkmaar between 2007 and 2009, and is United's fifth signing of the summer following the acquisitions of Memphis Depay, Morgan Schneiderlin, Matteo Darmian and Bastian Schweinsteiger.

"Sergio is a very talented goalkeeper," said Van Gaal. "He was a young keeper during my time at AZ Alkmaar and I am delighted he is joining Manchester United.

"He had a fantastic World Cup last summer in Brazil, although that is something I have put to the back of my mind! He will be a great addition to the team and I am looking forward to working with him once again.”

Romero's arrival is set to be followed by the departure of Victor Valdes. The Spaniard's attitude has been labelled a "big disappointment" by Van Gaal after he allegedly refused to play for United's reserves, and Valencia are in talks over a season-long loan deal.

Meanwhile, Van Gaal is hoping to keep David De Gea at United but has refused to rule out the possibility of the 24-year-old joining Real Madrid before the end of the transfer window.