Sunderland winger Sebastian Larsson feels victory at Chelsea gives them a fighting chance of beating the drop.
A return of four points from back-to-back away games has seen Sunderland gain ground on their rivals having also claimed a useful draw at Manchester City in midweek.
"Obviously it was a fantastic result today, you can't really say anything else," Larsson told SAFSee afterwards.
"It's the first time a Mourinho team has lost here in the Barclays Premier League, so of course it's a good achievement.
"We know the situation we're in; we're in desperate need of points. We've got four points from these two away games and given ourselves a chance - now we need to use it.
"We were very disappointed not to win at City, and to come from behind again today shows a lot of character and strength.
"This has given us a chance and hopefully we can take it."
