Chelsea's Frank Lampard fired the champions to a 2-1 victory over Aston Villa but there was a shock for Manchester United as they went down 2-1 at home to Blackburn Rovers on Saturday.
Chelsea's seventh league win in as many games gave them a double-digit lead over their main title rivals after United were stunned by two goals from Norwegian forward Morten Gamst Pedersen and Arsenal drew 0-0 at West Ham.
Charlton Athletic's charmed start to the season continued as they stayed second with a 2-1 victory at West Bromwich Albion and Bolton Wanderers are a surprise third after beating Portsmouth 1-0 in the late kickoff.
Newcastle United edged Manchester City 1-0 with a goal from England striker Michael Owen, while a wayward Everton suffered their eighth defeat in nine games this season in all competitions, losing 1-0 at home to promoted Wigan Athletic.
Liverpool needed a late penalty from France striker Djibril Cisse to draw 2-2 at Birmingham City.
But the extraordinary message from the day's action is that with the season barely a month and a half old, holders Chelsea are already looking like champions elect.
The team bankrolled by Russian billionaire Roman Abramovich are quoted by bookmakers at 1-7 on to retain their title.
They lead the table with 21 points from seven games, a Premier League record, ahead of Charlton (15), Bolton (14) and three clubs including Manchester United on 11 points.
Arsenal are seventh on 10 points.
Though they conceded their first league goal of the season, Chelsea's ability to exert pressure from midfield and up front enabled them to turn a tricky match around.
Chelsea manager Jose Mourinho told Sky Sports: "It was a very difficult game. They defended well but they didn't come to defend - they came to play the game.
"I think we deserved to win because we dominated, especially in the second half."
Brushing off the end of the clean sheets, the Portuguese coach said: "I'm not disappointed, it's not normal that we didn't concede a goal for so long.
"I said in my programme notes that if we concede a goal and win 2-1 I'll be very happy - and that's what happened."
Asked if Chelsea could let the title slip, Villa manager David O'Leary told reporters: "They'd have to lose a lot of players and Mr Abramovich go skint in January."
ANGEL'S TOUCH
Villa striker Juan Pablo Angel had a hand in both the first two goals, heading on keeper Thomas Sorensen's long kick for Luke Moore to squeeze home an angled shot in the 44th minute.
The Colombian turned villain just a minute later, though, breaking away from the Villa wall and allowing Lampard's free kick to soar into the back of the net.
The England midfielder made no mistake from the spot in the 75th minute after Villa's Olof Mellberg had checked Chelsea's Ivory Coast striker Didier Drogba in the area.
Manchester United will be reflecting on Paul Scholes's comments in midweek that their title hopes would be over if they failed to win their next two games against Blackburn and Fulham.
Pedersen gave Blackburn a surprise lead when his floated free kick ended up in the net through a packed area.
United, who used Wayne Rooney as a second-half substitute, drew level in the 67th minute when Rovers keeper Brad Friedel failed to hold a Rooney shot and Ruud van Nistelrooy pounced.
But Pedersen rifled home their 81st minute winner to secure a remarkable victor for manager Mark Hughes, a former Old Trafford favourite in his playing career at United.
Arsenal's title hopes suffered a setback as their injury-hit side - missing forwards Thierry Henry, Dennis Bergkamp and Robert Pires - failed to break down the Hammers at Upton Park.
"It's frustrating," said Arsenal manager Arsene Wenger. "We were quite stable defensively but we are not happy with what we did offensively - we created chances and couldn't take them."
