The right-sided winger has joined Newcastle United on a five-year contract for an undisclosed fee.

Gutierrez – dubbed "Spider-man" after donning a superhero mask during his goal celebrations – becomes the first signing of Keegan's second spell at St James's Park.

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And the 25-year-old said: "I cannot tell you how excited I am to be joining Newcastle United.

"The Premier League is a great place to play, and I cannot wait to meet my new team-mates and prove myself to the Newcastle United fans."

United beat off competition from a number of clubs to sign Gutierrez, who has two full caps to his name.

Keegan said: "Jonas is a wonderful signing for us.

"I know a lot of other clubs have been interested in him. He'll be a terrific addition to the squad.

"He's an exciting player and I'm sure our fans will enjoy watching him."

Jonas started his career at Velez Sarsfield in his native Argentina, helping the club win the Primera Division title in 2005 before moving to Spain.

He made his international debut against France in February 2007, and was in action earlier this month, playing in a World Cup qualifier away Brazil.

Jonas, however, will not be on Tyneside for the start of pre-season training on Monday.

He will instead have a break after his exertions for Argentina, and meet his new team-mates later this month ahead of an expected home debut in the pre-season friendly against PSV Eindhoven at St James's Park on August 6.

He could also face his former club Real, who United take on in the Mallorca Summer Cup at the ONO Estadi, Palma on August 3.