The Dutchman previously predicted that Chelsea would need to win every match to have any chance of catching Manchester United and, while he has duly delivered with nine points from three matches, it has made no impression on a gap to United that could be 10 points by Sunday morning.
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"Our first concern is our game of course against Manchester City," said Hiddink. "We have the possibility to watch. It will be a beautiful clash to watch and if Liverpool can do some harm then great because it will make for a more exciting end to the season. But United look very determined and if they win then they can do the same to Liverpool.
"When I said we could win the league we were on schedule at that time but United have not made any mistakes since and neither are we. Until it is impossible, then we will fight."
With senior Chelsea players, including Peter Cech and Michael Ballack, having expressed their hope that Hiddink will stay, the 62-year-old again reiterated his intention to return full-time to the Russia manager's job at the end of the season.
"I have made very clear a few weeks ago and more recently what will happen after the 30th May and we stick with that," he said. "If there is a good atmosphere then we like that and the attitude of players towards me is good.
"I didn't find any isolated group of players within the team. It's easy when you have won games to say as a manager that it has improved but I have not seen what happened before. It is more interesting to see the reaction when things have not gone well in one or two games than it is when you have won a few."
Of a rejuvenated Didier Drogba, he added: "I don't know what is different. I only saw him in the World Cup and after not so much in person but he is very committed for the team, he has responded very well to the team and contributes very well in the team."