Shaun Maloney has rejoined Celtic on a four-year contract from Aston Villa.
The 25-year-old made his Celtic debut in April 2001 but left for Villa Park in January 2007 for a £1million fee after failing to agree new terms with the Scottish champions.
Maloney has returned north for a fee which could rise to £2.5million, according to the Aston Villa website.
Maloney's return to Parkhead ends months of speculation about his future after he had failed to settle in the midlands under his former Hoops boss Martin O'Neill.
In his first spell at Celtic, the Scotland international made 138 appearances for the club, scoring 37 goals.
Team-mate Paul Hartley believes Maloney will have no problem settling back into life in Glasgow.
He said: 'It's a good move for him and a good move for the club.
'We are always looking to improve and he is another good player.
'We have a good squad as it is now and we know Shaun can play in a number of positions.
'He had a good spell at Celtic the first time so I'm sure he will do well again.'