League Cup: Jose Mourinho worried about Chelsea attack

Chelsea boss Jose Mourinho said he was concerned about his team's lack of goals as their profligacy in front of goal proved costly in their Capital One Cup exit to Sunderland.

Chelsea lost 2-1 in extra-time despite dominating the quarter-final tie.

"The quality of football we produced is amazing," said Mourinho.

"We never lost a match because we didn't play or that the opponent was stronger, it's just we don't kill opponents and we give them life."

The Londoners led through a Lee Cattermole own goal before Fabio Borini scored from an acute angle in the 88th minute to take the match to extra time.

Sunderland were the more threatening in the final 30 minutes and Chelsea were left to rue a number of wasted opportunities as Ki Sung-Yueng thumped in the winner.

Mourinho said a lack of killer instinct had been an issue throughout the season, pointing to Premier League defeats by Stoke,Newcastle and Everton as examples.

"Every other game - here, Stoke, Newcastle, Everton - every game we have lost, every game, it's the same story: chances and chances and football and football and not enough goals," he added.

"We need to score goals to finish opponents because we feel very comfortable on the pitch.

"The possession of the ball becomes easy, the creation becomes easy. We had big chances to score but we didn't.

"Maybe the way to rectify it is not to concede goals.

"Maybe the way is to have a different approach and not to concede goals because when you don't score enough goals, when you are a very offensive team and you don't score enough goals to win matches, maybe the right approach is to be more defensive, concede fewer goals and win matches with the few goals we score.

"But that's not what I want because that's not what we have in mind in the building up of this team. We want this team to play the way we are playing, we want this team to have evolution, but based on the football we are playing at the moment."