"But we had our worst defending of the season. It was a slack goal for us to lose," Manager Alex Ferguson said of Reading's 89th-minute goal.
"We resorted to playing safe football instead of playing the way we usually play," he said.
Manchester United now have 53 points from 21 games.
Chelsea draw derby game
|"The way we are defending, I don't know if we lost four points or won two points - four matches, eight goals conceded,"|
Jose Mourinho, Chelsea Manager
At Stamford Bridge, defender Moritz Volz put Fulham up 1-0 in the 16th minute by scoring the 15,000th Premier League goal since the competition began in 1992.
Defender Liam Rosenior deflected Frank Lampard's shot into Fulham's net in the 35th, before Didier Drogba scored his 20th goal of the season in the 62nd minute to put Chelsea 2-1 up. But defender Carlos Bocanegra equalised for Fulham with a goal in the 84th.
"The way we are defending, I don't know if we lost four points or won two points - four matches, eight goals conceded," Jose Mourinho, the Chelsea manager said.
Liverpool chase leaders
At White Hart Lane, Luis Garcia scored the winner against Tottenham as Liverpool posted its eighth clean sheet in nine games to stay 16 points behind Manchester United.
|Tottenham's Mido, right, and Liverpool's Daniel Agger |
battle for the ball [AFP]
In Saturday's other games: Bolton beat Portsmouth by 3 goals to 2; Blackburn led Middlesbrough from the start and ended the game at 2-1; Everton hammered Newcastle 3-0; West Ham lost their home game 0-1 to Manchester City and rejuvenated-Charlton beat a lack-luster Aston Villa side by Bryan Hughe's 90th-minute winner.
Watford's game against Wigan was abandoned because of a waterlogged field at Vicarage Road with the score level at 1-1.
Later on Saturday, Sheffield United will host Arsenal at Bramall Lane.