Chelsea boss Jose Mourinho is not yet ready to concede the league title to leaders Manchester United as the Blues prepare to face Arsenal on Sunday.
Chelsea have won two successive titles under Mourinho
Chelsea must win to keep the title race alive until Wednesday - when they take on United at Stamford Bridge.
"This season is not over," said Mourinho. "We've four matches to play, where we can win two more trophies.
"We can win one or none, but I think it is very important to show the nature of the players and their mentality."
United boss Sir Alex Ferguson will not watch the game between Chelsea and Arsenal.
"I won't be watching the game," said Ferguson, whose side moved eight points clear with a win at Manchester City on Saturday.
"I'll go for a game of golf. Hopefully, Arsenal will get the result we want, but if we have to go to Chelsea to get something we'll look forward to it."
Ferguson also revealed he had planned to go to watch United youngster Gerard Pique, who is on loan at Real Zaragoza in La Liga, but abandoned those plans because of a problem with the flights.
If Chelsea do not beat Arsenal then Ferguson will clinch his ninth Premiership title at the Old Trafford helm.
The Scot praised his players' character after they bounced back from the Champions League exit in Milan with a 1-0 win at Eastlands and Ferguson said: "What you saw today was human courage.
"The players showed great courage to come back from Wednesday and we are happy with 1-0.
"It wasn't a great performance but derby games are like that and in the end we got through it."
Ferguson paid particular tribute to Cristiano Ronaldo, who was stamped on early in the game by City's Michael Ball, but was tripped by the same player to earn the match-winning penalty, which the Portuguese winger dispatched.
"He was a victim of a really bad challenge early in the game and at that point it looked like the referee could have lost control," claimed Ferguson, who remonstrated from the touchline as match official Rob Styles waved play on after the incident.
City boss Stuart Pearce will review video replays of Ball's first challenge before deciding if any punishment is necessary.
"People have mentioned the tackle to me and are not particularly happy with what happened but I have not seen that," said Pearce.
"Certain things happen in games and people pick up on them.
"I will review the incident on video and will make any decision from there. We often leave decisions to referees and officials above them. It may be down to them."
Ferguson is on course for a ninth Premiership title with Man Utd
Pearce felt his side's failure to prise a point from the Manchester derby summed up their season.
Darius Vassell saw a penalty saved by United keeper Edwin Van der Sar and Pearce said: "We had a great opportunity to get equal and we missed it.
"Our problem all season has been putting the ball in the net. At the other end, defensively we've looked sound.
"Had we taken that opportunity I think we would definitely have got something out of the game."
Pearce defended his ploy of playing with only one striker, despite City's lack of goals this season.
"The bottom line is that when we chase the game we look vulnerable," he said.
"We stayed in the game right until the last minute, against the team who look as though they are going to be champions."