Chelsea manager Jose Mourinho maintains Manchester United are still genuine Premier League title contenders, but believes the festive programme could whittle down the opposition for the trophy.
Chelsea play Crystal Palace on Saturday and will bid to respond from last weekend's loss at Stoke and enter the weekend's fixtures trailing leaders Arsenal by five points.
Manchester United are 13 points adrift in ninth place, currently sixth of the six teams Mourinho counts as title contenders.
"They have to recover points not to one single team, they have to recover points to every other team," Mourinho said.
"It's difficult. Not just because it's 13 to Arsenal, but also because it's eight to us and to Liverpool and seven to City.
"But as I keep repeating, the culture of Man United is there, the power and the quality of their players is there, the tradition is there.
"When mathematically it's very possible, I never say Man United is out of the race."
Mourinho is well aware the results over the festive fixture programme can have a major say on the destination of the trophy come May.
"Let's see if after Christmas we can say instead of six (contenders), five," Mourinho said.
"Maybe one drops back or maybe one goes so up that it looks impossible to reach.
"It's very difficult to predict the way things are going. One thing is if we beat Arsenal, another thing is if Arsenal beat us. We can close the gap or they can open the gap.
"This weekend Tottenham-Liverpool, somebody loses points, us against Arsenal, somebody loses points, Arsenal against City, somebody loses points."
Chelsea's aim is to stay in contact.
Mourinho added: "Five points is a gap that is not a drama, but we have to try (to ensure) that the five-point gap doesn't open, at least.
"With a five-point gap (and) two matches (in) one week, everything can change.
"When you go instead of five to eight, nine, 10 (points), the situation is more complicated."
Mourinho, who won the title in 2005 and 2006 in his first two seasons with Chelsea, has long insisted the challenge on his return is more difficult, with a squad in transition.
He wants his players to have the mentality of one of the favourites, even if he believes other sides have a better title chance, after finding a team built for the short-term under his predecessor Rafael Benitez.
Mourinho added: "Benitez was chasing results. He was not worried about the building up of a team with a certain style. We didn't have a real base to start with.
"For many reasons we knew that the situation needs time and patience. We are competing against important teams in a very difficult league where you don't have one single easy match. We knew it would be difficult.
"We are not favourites, but we want to feel as favourites. We want to fight the favourites and we want to feel like we are.
"To put ourselves under a little bit of pressure only can help to be better. I want that."
Whether Mourinho is afforded the patience others have not at Chelsea remains to be seen, but what is in little doubt is that his side are favourites for Saturday's London derby with relegation-threatened Palace.
Defender Gary Cahill will be rested, with the upcoming fixtures in mind. Ashley Cole will return to the substitutes' bench, with Spain right-back Cesar Azpilicueta taking his place at left-back, and is instead selected for next week's Capital One Cup quarter-final at Sunderland.
Tony Pulis believes it is Palace's performances at home which will determine their Premier League fate and not games such as Saturday's trip to title challengers Chelsea.
The Eagles have won two of their three matches since Pulis' appointment, but the Stamford Bridge contest is the sternest test so far.
"I've come in, the players have responded and it's been a great few results and we're really, really pleased," Pulis said.
"But the season is not about three or four games - it's about the 23 that are left for us.
"Our season will be determined by our home form, from now until the end of the season.
"We've just got to make sure Selhurst Park is rocking like it has been the couple of times I've been manager there and that the players give everything they've got."
Pulis believes Palace can put the leading clubs under pressure at home, but it is more of a challenge away.
"On any given day, if Chelsea play to their maximum, they're a little bit ahead of us," added Pulis, whose former club Stoke beat Chelsea at the Britannia Stadium last weekend.
"The one thing everybody's really surprised about is that they haven't scored as many goals as maybe they should have.
"But they've played some fantastic football and they've got some top, top players.
"I think they're in a fantastic position and they're still fighting on four fronts.
"At Selhurst Park you can make it difficult and you can make it more of a competitive match. When you go away, it can be, in my experience, very, very difficult.
"The pressure is off us; I don't think anybody expects us to go to Chelsea and win the game.
"The important thing is the players go there and do their best, they enjoy the game and they enjoy the challenge."
Full-back Dean Moxey, one of three ever-presents for the Eagles this season, is doubtful for the Chelsea clash with a hamstring injury, but winger Yannick Bolasie is available following suspension.
A number of long-term injured are nearing returns as Pulis assesses his squad prior to the opening of the winter transfer window.