A 2-0 win over bottom side Sunderland made it five wins out of five for Jose Mourinho's side on a day that saw United held to a 1-1 draw by local rivals Manchester City and Arsenal slump to a 2-1 defeat at Middlesbrough.

Chelsea's win leaves them three points clear at the top of the table, although second-placed Charlton, who beat Birmingham 1-0 to maintain their own 100 percent record, have a game in hand.

Ruud van Nistelrooy's fifth goal of the season put United on track for victory in the 144th Manchester derby.

After flicking a Paul Scholes free-kick towards goal, the Dutchman pounced on the rebound after a fine save by City's former England goalkeeper, David James.

But City demonstrated how much more resilient they have become under Stuart Pearce when Joey Barton scrambled a 76th-minute equaliser to extend an unbeaten run that began at the tail end of last season to 13 matches.

For 45 minutes, Sunderland did a good job of containing Chelsea at Stamford Bridge.

But a half-time reshuffle by Mourinho, which saw Ireland winger Damien Duff thrown into the mix, produced a marked improvement which led to Cameroon midfielder Geremi putting the champions ahead nine minutes after the restart.

Didier Drogba made sure of the victory, heading home a Duff cross in textbook fashion with eight minutes left to leave Sunderland still looking for their first points since returning to the top flight.

Ominously for the pretenders to Chelsea's crown, Mourinho's men have yet to concede a single goal this season and, according to the manager, were well below their best on Saturday following the break for international matches.

Arsenal already trail Chelsea by nine points, albeit with a game in hand, and there was nothing in their performance on Saturday to suggest they will be capable of closing that gap.

Middlesbrough thoroughly deserved a victory that was secured by two cool finishes, the first from Nigerian striker Yakubu just before the break, the second from Massimo Maccarone. Jose Antonio Reyes scored a consolation effort for Arsenal in stoppage time.

Charlton's best start to a Premiership campaign has largely been down to the goals provided by Darren Bent.

The former Ipswich striker delivered his fifth of the season, a far post header after a quarter of an hour, to sink Birmingham at St Andrews.

Everton's early-season problems intensified after a frustrating 1-0 defeat by fellow strugglers Portsmouth at Goodison Park.

Despite dominating for long periods, the Merseysiders went down to a freakish own goal by big forward Duncan Ferguson, who left Nigel Martyn with no chance after connecting with a cross from Pompey winger Laurent Robert.

Michael Owen's hopes of a dream debut for Newcastle were dashed by Fulham, who claimed a fully-deserved 1-1 draw at St James' Park after taking a shock 13th-minute lead through American striker Brian McBride.

Newcastle did manage to score their first goal of the season but it did not come from Owen. Instead it fell to French midfielder Charles N'Zogbia to earn the point 12 minutes from time.