The Black Cats have just two points from the campaign and have yet to register a win and they never seemed likely to end that record against Chelsea despite loan signing Nicklas Bendtner making his debut.
The Blues cruised to a comfortable win despite the apparent close scoreline as Sunderland scored their consolation from Ji Dong-Won in injury time.
John Terry gave the Blues the lead after Mata's free-kick hit the outside of the post.
All of which heaps more pressure on Steve Bruce who must desperately convince the fans and board he is the right person to lead the Wearsiders.
Referee: Lee Probert
Venue: The Stadium of Light
TRIBAL ASKS: Blackburn’s Steve Kean was bookies favourite as the first Premiership manager to be sacked...perhaps we should now add Sunderland’s Steve Bruce to that list.
Yellow cards: Colback (SUN), Bosingwa (CHE)