David Luiz does not feel there are any major problems at Stamford Bridge, but accepts that it is vital Chelsea pick up three points at St James' Park this weekend.
The Blues have slipped 10 points off the pace in the Barclays Premier League following their recent poor run of form - a run which has seen them knocked out of the Carling Cup, and also fail so far to qualify for the knockout stages of the UEFA Champions League.
Luiz recognises that Saturday's trip to Newcastle and the European clash with Valencia which follows next Tuesday are both must-win games, if Chelsea are to keep their dreams of a successful season alive.
"We are not a team in crisis but the games with Newcastle and Valencia will be decisive for us," he told The Sun. "We have suffered a series of bad results and there has been a lot of pain in the dressing room.
"But now is the moment for take-off and we are determined to win our next few matches. We must beat Newcastle and Valencia to stay in with a chance of winning the Premier and Champions Leagues.
"But we're not thinking ahead to the Valencia game on Tuesday - our focus right now is Newcastle. They have been a revelation this season and have emerged as a rival similar in terms of danger to Manchester United."
Chelsea's slump has also meant that Andre Villas-Boas has come under increasing pressure, even though he says he has been assured over his future by owner Roman Abramovich.
One criticism aimed at the Blues under the stewardship of the Portuguese tactician is their defensive frailty - something that Luiz accepts part responsibility for - but has vowed to keep working hard to improve and repay the faith shown in him by Villas-Boas.
"This season has not been a positive one for me," added the 24-year-old. "But I intend to improve by working harder each day - and I'm hoping for a little more luck.
"AVB is a good coach but all coaches and players need a period to adapt to each other. The Premier League is a very hard competition and not is easy to offer top levels from the first day. But the season is long and Chelsea is a team that always takes its chances at key moments. So I remain very optimistic.
"People have been talking lately about crazy mistakes but I have a strong mentality. I am a very strong guy and these type of comments don't touch me. I have a great relationship with the supporters because I don't know how to be an actor."