Sebastian Coates
Sebastian Coates (left) has joined Sunderland on a permanent deal following a successful end to his loan stint on Wearside.AFP

Liverpool defender Sebastian Coates has completed his move to Premier League rivals Sunderland, both clubs confirmed via official statements released on their respective websites yesterday (1 July).

The 24 year old made 13 appearances for the Black Cats during a season-long loan spell in 2014/15 and now returns to the Stadium of Light on a permanent basis, signing a four-year contract for an undisclosed fee believed to be in the region of £2m ($3.1m).

Having joined Liverpool from Nacional in August 2011 following his success at that summer's Copa America , Coates struggled to establish himself at Anfield and featured just 24 times for the club in total.

He was not helped by a torn ligament in his right knee sustained while on international duty against Japan two years ago. He returned to his native Uruguay in January 2014 in order to prove his fitness ahead of the World Cup.

While he travelled to the tournament, Coates' involvement was limited and he was subsequently deemed surplus to requirements by Brendan Rodgers upon his return to Merseyside.

After agreeing to join Sunderland on transfer deadline day, he made his debut in the Capital One Cup third-round defeat to Stoke City, lasting just 45 minutes before being taken off due to a recurring thigh problem.

That particular setback kept him out of action until November and Coates was then mostly kept as an unused substitute under compatriot Gus Poyet before starting and completing the final six games of the campaign as Dick Advocaat successfully steered the club away from relegation.

"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," Sunderland sporting director Lee Congleton said.

"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."

Sunderland report that Coates, who will perhaps be best remembered at Liverpool for a stunning volley scored against Queens Park Rangers at Loftus Road in March 2012, will arrive in the north east next week after representing Uruguay at the 2015 Copa America in Chile.

Oscar Tabarez's side were unsuccessful in their quest to retain the trophy, squeezing through to the quarter-finals as one of the best third-place finishers before losing 1-0 to the hosts in Santiago.

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