For Chelsea manager Jose Mourinho, it has not been a merry Christmas.
Defending champion Chelsea heads into Saturday's London-derby against 12th-placed Fulham facing its toughest test since the Portuguese manager arrived at Stamford Bridge over two years ago.
Chelsea sits on 46 points, four less than league-leader Manchester United, which hosts Reading.
Injuries are beginning to play a bigger role in Mourinho's chase for a third straight title.
Chelsea and England captain John Terry underwent successful surgery on his injured back Thursday.
The defender was not expected to be available before the end of January at the earliest. However, in a surprise announcement, the club said Terry jogged at its training ground on Friday. Chelsea's doctor, Bryan English, declined to say when Terry would play next.
Starting goalkeeper Petr Cech is recovering from a fractured skull, No. 2 goalie Carlo Cudicini has a thigh tear, midfielder Joe Cole has a fractured foot and forward Arjen Robben is out after injuring himself in practice this week.
"This is a difficult period because we don't have the players to improve things, rotate and put pressure on other players," Mourinho said. "Right now, we are surviving because the distance to Manchester United is four points and that is not a drama. Manchester United must come to Stamford Bridge.
"But we are in a difficult situation, although I think we can survive."
Mourinho has even suggested moving striker Didier Drogba and his league-leading 12 goals to center-back as emergency cover.
"We cannot give the other teams the belief that they can score, that they can win," Drogba said. "Last season, and also two years ago, we were very strong when we scored one goal and the other teams could not think about coming back into the game.
"I do not like to play at center-back _ but I do it for the team because sometimes we have difficult moments in the game."
United goes into Saturday's clash against No. 9 Reading knowing it hasn't lost this season when forward Cristiano Ronaldo scores _ he's notched six in his last six league games.
"He is such a danger to defenders because he doesn't just beat men, he has the desire and drive not to give in when they foul him," manager Alex Ferguson said of Ronaldo. "No one enjoys playing against someone like that. I am sure Cristiano is already one of the best players in the world."
Ferguson, who turns 65 on Sunday, isn't desperate to sign players in the January transfer window.
"We may or we may not. It depends on a lot of things," Ferguson said. "But I am happy we have Henrik Larsson coming in and also with the improvement in Alan Smith."
In Saturday's other matches, Blackburn hosts Middlesbrough, Newcastle travels to No. 8 Everton, last-place Watford faces Wigan, and new manager Alan Pardew looks for Charlton to bounce back from a disappointing draw in his debut when Aston Villa comes to The Valley.
Arsenal is third with 36 points, ahead of Bolton on goal difference. Portsmouth is fifth with 35.
Liverpool hopes to rebound from a 1-0 loss at Blackburn that dropped it to sixth in the standings when it travels to Tottenham, which has won 12 straight at White Hart Lane.
"We won't look at the table. It's a waste of time," Liverpool manager Rafael Benitez said. "But we know we now have to play Tottenham and Bolton, who are in a league with us and very close together. We know how important it will be to beat these teams and stay in good position."
Unbeaten in six, Portsmouth welcomes Bolton and its French striker Nicolas Anelka, who has notched three goals in his last two games as the Trotters have won four straight.
The two sides have kept pace with Arsenal and Liverpool in the chase for a Champions League place.
"We all expect at the end of the day that it will be the big four clubs that will be there," Bolton manager Sam Allardyce said of the Champions League places.
"If any of us do any better and break into the top four, then it will be a minor miracle. But you never know in football. At the moment we're halfway through the season and in a good position."
Arsenal travel to Sheffield United without striker Emmanuel Adebayor due to a thigh strain.
Manchester City arrives at Upton Park to face No. 18 West Ham without midfielder Joey Barton, who is serving a three-match ban. Hammers defender Paul Konchesky will also miss the game due to a separate one-match suspension.
In the League Championship, leader Birmingham salvaged a point when substitute Neill Danns scored in stoppage time to forge a 2-2 draw with Luton.