Sunderland director of football Lee Congerton says he’d been tracking new signing Adam Matthews ‘for some time’ after completing the signing of the defender.
Matthews has put pen to paper on a four-year contract in moving from Celtic in a £2million deal.
The player is something of an unknown quantity but has been monitored closely by the Black Cats and will add valuable competition to head coach Dick Advocaat’s squad.
Congerton said: “Adam is a player we have been tracking for some time.
“Even though he is only 23 years old, he has a wealth of experience, and I am sure he will continue to improve under the leadership of Dick Advocaat.”
Advocaat added: “We know that we need quality players to improve competition for places in the side, so Adam is a welcome addition to our squad and we are very pleased to welcome him to Sunderland.”
Matthews began his career with Cardiff City, making over 40 appearances for the Welsh side between 2009 and 2011, before moving north of the border to Scottish giants Celtic, where he won four successive SPL titles.