Luis Boa Morte has joined West Ham from Fulham for an undisclosed fee, thought to be about £5 million. The Portugal international played more than 200 games for the west Londoners and was club captain at Craven Cottage.
Fulham manager Chris Coleman said: "I am of course disappointed that Luis has decided his future is not with Fulham FC. He has been a great servant to the club and we all wish him well.
"However, I have always said that if a player is not happy playing for this club and expresses a desire to go, then I would be prepared to let him leave; and this was the case with Luis.
"Having discussed this with the chairman and the managing director, we believe it is in the best interest of the club to invest in players who are prepared to commit their future to us."
Coleman added: "We will continue to add strength and depth this window and, if necessary, the next, to ensure that we have a strong enough squad of players for the future to enable us to push on as a club, which remains our ambition."
The 29-year-old played 250 games for Fulham, scoring 54 goals after joining from Southampton in a £1.7 million deal in 2001. The Lisbon-born player began his Premiership career with Arsenal.
Wigan manager Paul Jewell has completed his third signing of the transfer window with the capture of defender David Unsworth from Sheffield United.
Unsworth has completed a free transfer from the Blades where he has spent the last 18 months, although the experienced 33-year-old has recently been out offavour under boss Neil Warnock.
Jewell said: "David is a highly experienced player, who has been there and done it as a player. He will add defensive cover right across the back four.
"He's a canny sort of player, he has great knowledge of the game at this level and most importantly, it's another body in there, who I know will give 100 per cent every time he puts on the shirt.
Unsworth added: "I'm delighted to sign for Paul Jewell and Wigan. They are a big club with great ambition and I hope to be able to play some part in their story."
