Newcastle, having paid a club record amount for Michael Owen, were also involved in the second biggest deal of the final day of the summer transfer window with Jermaine Jenas joining Tottenham Hotspur in a £7million deal.
Jenas, who is part of England's squad for the upcoming World Cup qualifiers against Wales and Northern Ireland, has agreed a five-year contract.
He will be joined at White Hart Lane by the South Korea full-back Lee Young-Pyo, who has signed a four-year deal subject to a work permit being granted.
Jenas, who was expected to leave St James' Park after saying that playing for Newcastle was "like living in a goldfish bowl", will face competition from Michael Carrick and Edgar Davids in the centre of Tottenham's midfield.
Graeme Souness said of Jenas: "I'm sad he's gone, I didn't want him to go, I enjoyed working with him. It was his decision, he's joined a great club in Spurs. He's a good lad. I was never told I had to get anyone out to get Michael in."
"We want young players at this club," said the Tottenham manager Martin Jol, "and if they are already internationals like Jermaine it is always a very good thing for us. I think Jermaine will develop into a great player."
However, Tottenham failed in their attempts to procure Cristiano Lucarelli from the Serie A club Livorno despite increasing their original offer to £3.4million for the striker.
Lucarelli, who was the leading scorer in Italy last season, expressed his desire to join Tottenham but Livorno's president Aldo Spinelli refused to sanction any move, dismissing Spurs' offer as "a joke".
"Lucarelli is a crucial player for us," said Spinelli. "He is under contract for five more years, and there's no price that will make me change my mind."
Lee Young-Pyo, who Jol hailed as "the best left-back in Holland", will fill the void left by Erik Edman after the Swede joined the French club Rennes on a three-year contract.
Reto Ziegler is also on his way out of White Hart Lane after joining Hamburg on loan for the remainder of the season.
Meanwhile, Peruvian midfielder Nolberto Solano was on the verge of making a shock return to Newcastle last night just 19 months after leaving for Aston Villa.
The 30-year-old winger was undergoing a medical last night after the two clubs agreed an undisclosed fee, believed to be in the region of the £1.5million for which he initially moved, with James Milner travelling in the opposite direction on loan for the rest of the season.
Newcastle confirmed the development, although with time running out before the closure of the transfer window at midnight last night, they were working desperately behind the scenes to complete the deal.
The former Boca Juniors player was signed by Kenny Dalglish for £2.5million in August 1998 and proved hugely popular as he and Frenchman Laurent Robert set about the task of providing the supply lines to Alan Shearer.
However, he fell out with Bobby Robson over his frequent and lengthy trips to South America to represent his country after at one point agreeing to put his international career on hold, and he was eventually sold to Villa in January last year.
Robson's replacement Graeme Souness attempted to resign him during the last transfer window, and looked set to get his man at the second attempt.