West Ham have completed the signing of Birmingham defender Matthew Upson for an initial fee of £6million.
The 27-year-old England international has agreed a four-and-a-half year contract at Upton Park - becoming Alan Curbishley's sixth signing during the January transfer window.
He goes straight into the squad for the Hammers' Premiership clash at Aston Villa on Saturday.
The Hammers had already seen offers of £4million and £6million rejected by Blues boss Steve Bruce and the board of directors for Upson.
But it was believed they would make a further attempt to sign the former Arsenal player, who made it clear he wanted to leave St Andrews after four years.
And tonight's deal, which could rise to £7.5million depending on appearances, proves how determined Alan Curbishley was to continue strengthening his Barclays Premiership strugglers.
Bruce had been adamant Upson would not be sold for even £10million, because he feared the 'negative effect' his departure would have on the squad of losing the England player.
But Upson accused Birmingham of 'moving the goalposts' and believed the fee they wanted for his services was unrealistic, given he has only 17 months to run on his five-and-a-half-year contract.
His representative Barry Neville accused Blues of 'reneging' on a verbal agreement to allow Upson to leave if a certain price was met by any interested parties.
The move is not entirely surprising, considering Upson had already stated he will not sign a new contract for Birmingham even if they were promoted to the Premiership.
Arsenal paid Luton £2million in 1997 for the services of the Suffolk-born defender.
After waiting patiently for his big chance under Arsene Wenger, Upson won a Premiership title medal in 2001-02, but continued to find first-team opportunities limited at Highbury.
After loan spells at Nottingham Forest, Crystal Palace and Reading, Birmingham paid £1million to make him a permanent signing in January 2003.
The former England Under-21 international won a call-up to the full national team and made his debut in a friendly against South Africa in Durban on May 22, 2003.
Upson went on to win seven full caps under Sven-Goran Eriksson, the last of which came in a 1-0 friendly defeat against Spain at the Bernabeu stadium in November 2004.
He suffered from injury problems during his time at St Andrews - missing nine months with a snapped Achilles tendon - but made 130 league and cup appearances for Blues, the last of which was last night's 3-1 Championship defeat at the hands of struggling Southend.