Liverpool defender Sebastian Coates will challenge John O’Shea and Wes Brown at Sunderland

Coates became the first Uruguayan to arrive at the Stadium of Light during Poyet’s Sunderland tenure after joining on a season-long loan from Liverpool on transfer deadline day.

The 23-year-old watched last weekend’s draw against Spurs from the stands after being primarily limited to light training last week, as he makes his way back to full fitness.

But Poyet rates Coates highly after recommending the centre-half to Liverpool in the summer of 2011, when he was then in charge at Brighton.

And the Sunderland head coach says that when Coates does eventually get his chance – probably in next week’s Capital One Cup third round tie against Stoke – he needs to put pressure on first-choice defensive pair O’Shea and Brown.

Poyet told SportMail: “Sebber is my first Uruguayan here. I had one (on-loan Stoke midfielder, Diego Arismendi) for a month at Brighton.

“I know Sebber, I recommended him to England in the beginning when he came to Liverpool.

“He was a 6ft 3in centre-half, calm on the ball and with aggression.

“He’s a good player.

“Slowly, he’s going to have to start competing with Wes and John, and when he has the chance to play in any game – even in the cup – he needs to perform.

“I think it’s a great chance for him as well, and a great challenge.

“We needed a centre-half too, so it works both ways in helping each other.”

Coates arrived at Liverpool in a £7million deal from Uruguayan side Nacional after forging a reputation as one of the brightest prospects in South America.

But he started just six Premier League games before suffering cruciate ligament damage in August 2013.

Coates spent the second half of last season back on loan with Nacional, before Liverpool made him available this summer.

“From what I know, his progression (at Liverpool) was well-explained when he went there,” added Poyet.

“They were looking for a young centre-half to have a year behind (Jamie) Carragher and company, to learn English football and adapt.

“And then, it’s football.

“They changed the manager, a new group came in, Carragher stayed another year, and then an injury, and you find yourself in a different situation.

“When he came, he came with that kind of programme for his career. Everything was clear.

“But then everything changed.

“He just needs to understand what we do now, and then it’s up to him.”