Serbia's Novak Djokovic, the world tennis number one seed, has a back injury and hinted to a Serbian paper Tuesday that he might miss the China Open and the Shanghai ATP masters 1000 in October.

"I have a partial tear of a (back) muscle which needs rest (...) it is hard to say how much time off I need after only one exam, we will determine that in the days to come," Djokovic told the sports daily Sportske Novosti.

Real Madrid coach Jose Mourinho, stung by a shock 1-0 loss to Levante, accused the winners of acting and said his own players aren't comfortable with the "dirty side" of football.

Mourinho, whose side played much of the game with only 10 men after Sami Khedira got sent off for a second yellow card, blasted the referee, his own players and most of all the Levante style of play.

Manchester United beat title rival Chelsea 3-1 Sunday for its fifth straight victory in the Premier League, and Manchester City squandered a two-goal lead in a 2-2 tie at Fulham.

Wayne Rooney added to goals by Chris Smalling and Nani before missing a penalty kick, helping United (5-0) maintain its perfect start to the defense of its title. United won its 18th consecutive Premier League game at Old Trafford.

Manchester City manager Roberto Mancini insists he is still short of players despite splashing out a whopping £210 million since taking charge of the English Premier League club.

City failed to protect a 2-0 lead on Sunday and were pegged back to 2-2 by Fulham at Craven Cottage.

Sunday's rain at Chicagoland Speedway forced NASCAR to postpone the opening race of the Chase for the Sprint Cup championship.

NASCAR rescheduled the race for Monday at noon Eastern.

Spanish superstar Rafael Nadal again blasted the International Tennis Federation on Sunday, claiming they were shirking their responsibility to players by failing to lighten a packed tennis calendar.

Nadal led Spain to a 4-1 Davis Cup win over France, and a final date with Argentina, but there were tears for his U.S. Open final slayer Novak Djokovic whose injury-forced retirement saw defending champions Serbia slump 3-2 to the South Americans.

Chelsea manager Andre Villas-Boas has revealed France striker Nicolas Anelka is set to leave Stamford Bridge at the end of the season.

Anelka's contract expires at the conclusion of the current campaign and Villas-Boas claims the former Arsenal and Real Madrid star has indicated he is prepared to run down his current deal.

Bayer Leverkusen's Germany goalkeeper Rene Adler is expected to miss the rest of 2011 as he recovers from knee surgery, his club coach Robin Dutt revealed on Sunday.

The 26-year-old is recovering from a knee operation in July, but Dutt says he does not expect to have Adler back in the team until January with the Germany shot-stopper set to miss Leverkusen's remaining Champions League group matches as a result.

England players are pampered and after the "complete disaster" of their 2010 World Cup campaign have no chance of winning Euro 2012, former England midfielder Paul Scholes claimed on Saturday.

The ex Manchester United star also hit out at managers who he believes take on the national team job for the money.

Swiss star Roger Federer said he felt "completely beat up" following his Davis Cup doubles tie on Saturday, a day after Rafael Nadal blasted the packed tennis calendar.

The current round of Davis Cup matches began just days after the end of the U.S. Open, prompting Nadal to complain that players' physical wellbeing was at risk.