DAVID LUIZ: COLLECTIVE EFFORTS

David Luiz believes the defensive improvement throughout the team over the last couple of months has enabled us to put together a sequence of results which has taken us to the top of the Barclays Premier League table.

The Blues travel to West Bromwich Albion tonight unbeaten in 11 games in all competitions and having conceded just two goals in the same period.

The Brazilian, who has been used in midfield and defence in recent weeks, is well placed to assess the way in which our fortunes have improved since exiting the Capital One Cup in early December.

'It's always important to keep a clean sheet because it enables us to give a platform to the more attacking players to hurt the opposition,' he tells the official Chelsea website.

'That's our job and it makes me very happy when we are able to do that, but it's not just about the defenders, it's down to the whole team. It's because everybody, the strikers and midfielders, along with the back four, are working hard for the team.

'We are a big club, we want to win and we want to play well in every game. Sometimes that's possible but sometimes it's not. We work hard every day and we want to improve; some people pay attention to numbers and statistics but all we can do is look to improve every day in training. That's our mentality and that's the way we want to continue to be.'

The Hawthorns hasn't been a happy hunting ground in recent years, with the Blues falling to defeat on our previous two visits. Pepe Mel's side have been struggling for form of late, but they remain a serious threat in front of their own supporters, as Arsenal and Liverpool have found this season, with both teams forced to settle for a point.

Having spent much of the campaign hunting down the likes of Arsenal and Manchester City, Jose Mourinho's side now lead from the front, ensuring the players are presented with a different type of challenge.

'When you play for a big club there is always pressure,' says the 26-year-old. 'From the first day of the season until the last, it's natural. Manchester City and Arsenal both have excellent teams but the most important thing for us is to just concentrate on ourselves. We just need to do our job in the right way, work with humility and continue the way we are playing.

'It's a tough game, we've lost on our last two visits and when we played them earlier in the season we scored a late equaliser. They are a good team and when they play at home there is always a big atmosphere. It's very difficult to play there so we need to go there with the right mentality and produce a top performance if we want to win the game.'

David Luiz, now an experienced member of the squad after moving to the club from Benfica over three years ago, also praised the recent impact made by two of his team-mates, Willian and Nemanja Matic.

'Willian is my friend from childhood, from the age of eight, and it's a great gift from God to be able to play together now,' he says. 'I'm so happy for him because, with every day, he is improving and showing everybody the talent he has.

'He's a player who works hard every day and wants to improve. He's one of the key players in the team right now. He's a great guy, I know his family and I know the atmosphere in which he likes to live, he has a fantastic heart.

'I've been very impressed with Nemanja and I know how he likes to play because he learnt from the same philosophy as I did at Benfica. He's a fantastic player, that's why he came back to the club.

'He gives us different qualities in the middle of the pitch; he's strong, he fights for the ball and he has a fantastic left foot. He's another great player in our team and that makes me happy, I don't mind if I play by his side, behind him or even in front of him.'

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