David Luiz has said that he will take both criticism and praise in his stride as he concentrates on just doing an "honest" day's work at the heart of the Chelsea defence.

The wild-haired Brazilian centre-half has become something of a cult figure at Stamford Bridge following his £21m move from Benfica just over a year ago. The 24-year-old has produced solid displays as well as the odd eccentric performance – one of which, in a defeat by Liverpool, causing the Sky Sports pundit Gary Neville to declare that Luiz looked as if he had been "controlled by a 10-year-old in the crowd on a Playstation".

As Chelsea look to replace the disappointment of letting a 3-0 lead slip against Manchester United last weekend with a positive result at Everton, Luiz said meeting his own work ethic was all that matters.

"I have been working in the same way as always, training at my best level," said Luiz, whose goal had put the Blues into a seemingly commanding position at the start of the second half before United launched a fightback to snatch a share of the points. "Sometimes you get criticism, like I did, and recently I have been applauded for my work. As long as I can go home and lay down on my bed and have my conscience clear that I am doing an honest job, I am happy."

Luiz added: "The main thing is to continue working and maintaining the philosophy that the coach instructs. We have to do this, sometimes we are doing things that are great and not getting the results and sometimes we do things not so good and get the result.

"The main thing is to continue working hard. Obviously we are not where we want to be at the moment, not fighting for first place, but we have to keep looking for victories and believe in ourselves. There are games we have lost where we could have done better, but we can't change the past, we can only look to the future and know that we can do better and move up positions."

Chelsea could have Frank Lampard available again this weekend, the England midfielder having returned to train with the squad for the first time since injuring his calf against Norwich on 21 January. John Obi Mikel has also resumed full training after seven weeks on the sidelines because of a hamstring problem. The full-back Ashley Cole has served a suspension, but captain John Terry (knee) remains a doubt.

The club's owner, Roman Abramovich, was understood to have again attended training yesterday – his third recent visit to Cobham. The club, though, has already denied any suggestion that manager Andre Villas-Boas was coming under increased scrutiny from the billionaire owner.

Chelsea are aiming to fall in line with Uefa's new financial fair play rules and recently announced a total loss of £67.7m for the financial year ending 30 June 2011. Accounts have now been made available at Companies House, and show revenue rising by 8 per cent, with a 2.6 per cent fall in wages.

However, the next six months will see the "amortisation charge" – which is how transfers spending is recognised across the life of a player's contract – go up to take into account the deal for Luiz and Fernando Torres, signed for £50m in the same January window last year. The club's overall operating loss had reduced from £70.9m to £67.7m.

Uefa's new rules which will aim to curb football's finances are set to kick in from 2013-14.Clubs hoping to take part in the Champions or Europa Leagues must balance expenditure over a three-year period, but will initially be allowed to make a loss of £37.5m falling to £25m from 2015/16.