Sunderland head coach Dick Advocaat secured his first signing on Wednesday evening when Liverpool defender Sebastian Coates completed a permanent switch to the Stadium of Light.

The 24-year-old Uruguay international, who had a year remaining on his contract at Anfield, has signed a four-year deal and joins for an undisclosed fee understood to be in the region of €3 million.

Sporting director Lee Congerton said: "Sebastian was an important part of the team under Dick last season and we are delighted that he has joined us on a permanent basis.

“He has Barclays Premier League experience, which is important and, after spending last season on loan with us, he will be able to settle into the team very quickly.”

Coates joined Sunderland on loan for the season in September last year under then head coach Gus Poyet, but initially struggled to make his mark at the Stadium of Light.

However, he played every minute of the club’s final six games of the season, in the process taking his tally to 13 appearances, as the Black Cats dragged themselves out of relegation trouble and did enough to persuade Advocaat he had a future in the north-east.

He is the first of what the Dutchman will hope is an influx of signings this summer as the 67-year-old attempts to strengthen his squad in terms of quality rather than numbers after a chaotic few years in the club’s history.

Former director of football Roberto de Fanti drastically overhauled the squad two summers ago during Paolo di Canio’s ill-fated reign, and Congerton conducted a second overhaul 12 months ago in an effort to address the deficiencies of his predecessor’s scatter-gun approach.

The latter continues to work away on a series of further targets, while Advocaat has put his contacts in world football to good use too as they attempt to bolster the current crop of players.

Meanwhile, the former Netherlands boss has confirmed his backroom staff and as expected, long-time ally Bert van Lingen will not re-join him on Wearside.

However, Zeljko Petrovic, with whom he also worked during his spell in charge of the Serbia national team, is back on board and former England midfielder Paul Bracewell, who stepped up from the club's Academy ranks during Advocaat's initial nine-game reign at the end of last season, will continue as first-team coach.

In addition, Adrian Tucker will remain as goalkeeping coach and there is a place on the staff too for sports scientist Scott Pearce.