Manchester United striker Dimitar Berbatov believes Chelsea are the only team who can prise the Premier League title away from Old Trafford.
Speaking ahead of Sunday's clash at Stamford Bridge, Berbatov told MUTV: "They will be our main title rivals.
"I always think Manchester United and Chelsea will be the top two and I don't think this year will be any exception.
"They have great players and a great coach. It is still early but I think the title will be between us two."
Victory on Sunday would allow United to leapfrog Chelsea into top spot ahead of the international break, but they have not won at Stamford Bridge since 2002.
Berbatov has four goals in 10 games against Chelsea, including a penalty for Tottenham during the 2008 Carling Cup final which helped Spurs lift the trophy.
"I scored plenty of times against them with Tottenham, now I want to continue with Manchester United," said the Bulgarian.
"I would be glad to score a couple against them tomorrow but it is not about one player.
"If it was 1-0 and Nemanja Vidic or Patrice Evra got the goal it would be just as good because we would be taking the three points home and we would be above them again."
With that in mind, Chelsea manager Carlo Ancelotti has instructed his side to take a leaf out of Liverpool's book and smother United's midfield.
Sir Alex Ferguson's side lost 2-0 at Anfield two weeks ago, and Ancelotti insists the Blues must match the work ethic shown by Rafael Benitez's engine room that day.
"Liverpool played a fantastic match and put a lot of pressure on them," said Ancelotti.
"That's why they won. It was a good lesson as United suffer with pressure on their midfielders."
Ancelotti is eager for his side to extend their two-point lead over United at the top of the table, but has played down the hype ahead of one of the most eagerly-awaited games of the season.
"Psychologically, it will not mean more," the Italian insisted.
"We have to play against a strong team. We will play against the second team in the Premier League, but I think that it's just a game that carries three points like the others.
"But it is important because we play against a fantastic team, we know that it will be a very difficult match but also a very interesting one."
The former AC Milan coach also hailed counterpart Ferguson's reign at Old Trafford, adding: "He has done a fantastic job with this team.
"For a coach to stay such a long time with one team is very difficult, not only in England but everywhere.
"In Italy it would be impossible, for sure. He's a very important man for the history of this club. United have a fantastic history and Ferguson is one of the most important men in this history."
United boss Ferguson insists he is not surprised by Ancelotti's impressive start in English football.
"I thought Ancelotti would do well," said Ferguson.
"He was a great coach at AC Milan. He won the European Cup twice and brought a wealth of experience with him to Chelsea.
"He was also a great player so he has a lot of knowledge. He brought a different system to the ones Chelsea have used in the past."
Ferguson added: "We have to get our act together because our record down there has not been good for the last six years.
"It is a strange situation because we used to have a terrific record down there up until a few years ago. But we have let it slip.
"The players all realise it is going to be a big game and their performance is going to be important."
Meanwhile, Chelsea left-back Ashley Cole has revealed winning the Premier League title is his main target this season.
"To go through 38 games in the league, beating these teams - the likes of Arsenal, Man United, Liverpool, Tottenham and Man City - it's so hard to win it and I would feel more if we could do it," the England defender said.
"A lot of teams have strengthened their squads so to win it now you have to be a good team."