Gus Poyet has hailed the impact of Fabio Borini and Ki Sung-Yueng, after Sunderland's 2-1 victory in the League Cup over Chelsea.

The two players came on as substitutes in the second half and scored the goals that sent the Black Cats through to the semi-finals, with Poyet delighted with the positive contributions they made.

"That's why Fabio is so important for us because sometimes he doesn't find himself in the team for different reasons, but as soon as he gets on he affects the game and credit to him," he told the club's official website.

"Also Ki, you don't see him scoring too much but now he's playing further forward I think he's going to give us that extra quality near the box, so they've done very well.

"You need players [like that]; sometimes they are on the bench and they are not happy but then they become the heroes and then they go home really, really happy. Let's see if we can maintain this confidence ahead of Saturday."

Sunderland host Norwich City in the Premier League on Saturday.