Gus Poyet says this weekend's game against Chelsea will be 'the biggest challenge so far' for Sunderland.
The Black Cats welcome Chelsea to the Stadium of Light on Saturday, with Jose Mourinho's side sitting top of the Premier League and currently unbeaten in all competitions this season.
Chelsea beat German club Schalke 5-0 away in the UEFA Champions League last night, with a performance which Mourinho described as 'perfect'. Speaking ahead of Saturday's match, Poyet said:
Middlesbrough defender Kenneth Omeruo has expressed his delight over his return to the club.
The 20-year-old, who spent the second-half of last season at the Riverside, has re-joined Middlesbrough on a season-long loan from Chelsea.
Omeruo played in all four of Nigeria's games at the World Cup in Brazil.
Middlesbrough boss Aitor Karanka has expressed his delight at the club's loan deal for defender Kenneth Omeruo.
The 20-year-old has re-joined Boro on a season-long loan from Chelsea.
Boro's Head Coach said:
Middlesbrough have re-signed Chelsea defender Kenneth Omeruo on a season-long loan.
The 20-year-old made 14 appearances for Boro last season after joining the club on loan in January. The Nigeria international impressed during his previous spell and will now spend the new campaign back at the Riverside.
Omeruo featured in all four of Nigeria's matches at the 2014 World Cup in Brazil.
Kenneth Omeruo returns to the Riverside after a successful loan spell last season. Middlesbrough FC announced the signing of the centre back, adding that it's down to the fans.
Newcastle take on Chelsea at Stamford Bridge tomorrow (February 8).
Manager Alan Pardew says while they have won there before, but he is under no illusions about how difficult the competition will be from Jose Mourinho's side.
Middlesbrough have confirmed the loan signing of highly-rated Chelsea defender Nathaniel Chalobah.
The 19-year-old, who has 12 caps with England under-21's, will spend the remainder of the season at the Riverside.
Anzhi Makhachkala boss Guus Hiddink has dismissed speculation that the club are planning a summer move for Chelsea striker Fernando Torres.
The Spain international has struggled to recapture his best form since his £50 million move from Liverpool in January 2011, leading to reports that the European Champions may try to offload the 28-year-old in the near future.
The Russian club have been linked with Torres in recent newspaper reports. However, Hiddink has moved quick to play down the rumours.
Speaking ahead of his side's Europa League match with Newcastle United, he said: "Well it's interesting. With Anzhi it means that it's always 'oh the club has a lot of money', or 'the club has a lot of prestige'.
"Everyone is linked who wants to make a move, or an agent who wants to make a move. It's a game. As journalists, you know better... Maybe not better, but equally as coaches do.
"Players or agents have sometimes interests to be linked to other clubs, or to get a better contract on their own or whatsoever. You know what will happen. As long as there's nothing official from our side I can assure you there is no single approach to any player at this moment."