Posted on: Fri 30 Mar 2012

Just under a year ago David Luiz scored his first Chelsea goal to kick-start a comeback against Manchester United at Stamford Bridge.

It was a night of raw emotion in west London, the Brazilian equalising Wayne Rooney's first-half opener before Frank Lampard converted a late penalty after Yury Zhirkov had been felled by Chris Smalling.

Eleven months on the former Benfica defender concedes we are unlikely to figure in an exciting title race as we did last year, but is determined to show just how good we are this afternoon.

'From last season to this season things have changed, both teams have new players and squads, some things have not gone so well for us but we have to keep working hard and doing what we have been. We have not been getting the luck, so we have to keep working hard.'

United's attacking options may seem daunting, with Wayne Rooney, Dimitar Berbatov, Javier Hernandez and Danny Welbeck all fit, but David Luiz believes there is enough quality in the Chelsea dressing room to worry the champions.

'Manchester United have great players all over the pitch, they're a world-class team,' he said, 'but Chelsea are too and Sunday will be an excellent game because of this.

'I watch them a lot, this is my job, my life, so I see a lot of them and I know well enough their strengths.

'They always enter competitions to win them, they have a winning mentality, but it is just the same here, every competition Chelsea enters is to win and I can't see a time in the future when these two teams are doing anything different.'

Tuesday night's 1-1 draw at Swansea brought to an end a run of four consecutive clean sheets for the 24-year-old and his team-mates, and with Ashley Cole suspended and John Terry ruled out through injury it seems manager Andre Villas-Boas will need to juggle his resources, and could mean a debut for Gary Cahill alongside David Luiz.