Shaun Maloney has completed his £1m switch from Celtic and signed a three-year contract with Wigan Athletic.
The 28-year-old ends his second spell with the Glasgow club after a previous stint in England with Aston Villa.
The Latics have also signed Chelsea's Dutch defender Patrick van Aanholt, 21, on a season-long loan.
Wigan chairman Dave Whelan said: "Roberto Martinez rates Shaun very highly and has every faith that he will do well."
"The player maybe has something to prove after his last spell. We're all excited about seeing him in action."
Maloney joined Villa from Celtic in January 2007 before returning to Glasgow in 2008.
The Scotland international declared at the time of his return that it had been a mistake to move to Villa, where he failed to become a regular starter amid injury problems.
However, Whelan says manager Martinez is sure Maloney can be a success in England second time around.
"Roberto is a big fan of Scottish football lads," Whelan said on Tuesday. "He knows they've got a big heart and he knows they fight.
"And, once they adjust to the pace of the Premier League, we've had some very good lads from Scotland.
"Roberto is an excellent judge of football and footballers.
"If Roberto says to me that he thinks this lad can make it, I am 99 per cent sure that the lad can make it."
Maloney, who can play on the wing or up front, captained Celtic for a period in late 2010 in the absence of the injured Scott Brown.
However, he was taken off injured during a 2-2 draw with Inverness Caledonian Thistle on 27 November and required surgery on an ankle injury.
Current Celtic manager Neil Lennon restored Maloney to the squad for a 1-0 win at home to St Mirren in April, but he has since struggled to earn a regular starting position.
Celtic striker Anthony Stokes admitted to be "surprised" at Maloney's imminent departure but wanted to wish his outgoing team-mate well.
"Shaun is a top player and he's a great player to have around the place," said Stokes.
"I want to wish him the best, he's been a top professional and a great player so I wish him all the best if it's all done."
Now he could become Wigan's second addition within 48 hours after .
News of Maloney's likely departure came as .