Gutierrez, nicknamed "Spiderman" because of his distinctive goal celebrations, has joined the Magpies from Spanish side Real Mallorca on a five-year deal for an undisclosed fee.

The 24-year-old – he celebrates his 25th birthday on Saturday – will join up with his new team-mates after a short break following his post-season exertions with his country, which ended with a 0-0 World Cup qualifying draw in Brazil on June 18.

Keegan will hope Gutierrez's arrival is the first of several over the next few weeks as he attempts to drag the club back into the top half of the Barclays Premier League table.

However, it is understood the right-sided midfielder's capture does not mean the Magpies are ready to re-think their decision to keep James Milner at St James's Park amid persistent links with both Liverpool and Aston Villa.

Keegan was delighted to have made the breakthrough after weeks of foraging by executive director (football) Dennis Wise and vice-president (player recruitment) Tony Jimenez.

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

"I know a lot of other clubs have been interested in him. He will be a terrific addition to the squad. He is an exciting player and I'm sure our fans will enjoy watching him."

Jonas, who began his career in Argentina with Velez Sarsfield, is determined to prove himself in front of fans who have been waiting patiently for new signings to arrive.

He 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."

Transfer dealings are rarely straightforward in the modern era, but the announcement of Jonas's capture came just 24 hours after Mallorca revealed they had launched a claim for compensation of 15million euros.

The claim is over the player's earlier decision to unilaterally terminate his contract with them under Article 17 of Fifa's transfer regulations.

Sporting director Nando Pons said: "We are asking for 15million euros for the unilateral termination of the contract without just cause.

"It's a legal matter. We are not happy about it in the slightest, but Mallorca has to protect its interests."

Newcastle are due to meet Mallorca, who have held talks with former Magpies chairman Freddy Shepherd over a possible takeover, in the Mallorca Summer Cup on Sunday, August 3.

Gutierrez, who had previously been linked with Portsmouth and Manchester City, will hope to make a bigger impact at Newcastle than fellow Argentinians Christian Bassedas and Daniel Cordone.

He must also surely do better than Newcastle's last arrival from Mallorca – £5.8m flop defender Marcelino.