Defender Mikael Silvestre and winger Ryan Giggs scored the goals that ensured United are the only side with a 100 percent record and kept them two points clear of second-placed Everton.
Everton, down to 10 men for an hour following a red card for Kevin Kilbane, fully deserved a 2-0 win over a pale Tottenham Hotspur side at White Hart Lane with an own-goal by Calum Davenport and an Andy Johnson strike.
Champions Chelsea, six points adrift of United after one win and a defeat, play at Blackburn Rovers on Sunday, when Newcastle United also visit Aston Villa.
There were two red cards and two penalties at the Valley where home side Charlton Athletic spent more than an hour a man short after Hermann Hreidarsson was sent off for violent conduct but still beat Bolton Wanderers 2-0 for their first win.
Striker Darren Bent scored both goals, the first from a penalty in the 65th minute, nine minutes after El-Hadji Diouf had his saved by Scott Carson and six before Davies became the second player dismissed.
In the day's early match Liverpool scored twice in four minutes to come from behind and beat West Ham United 2-1 in a re-match of May's FA Cup final.
Striker Bobby Zamora scored his fourth goal in three matches to give Hammers an early lead, Danish defender Daniel Agger equalised in the 42nd minute with a fine shot from 30 metres and Peter Crouch struck the winner four minutes later.
The result gave Liverpool four points from two matches.
The two other promoted sides also lost. Wigan Athletic beat Reading 1-0 and Fulham defeated Sheffield United by the same score.
Arsenal visit Manchester City later on Saturday.