(CNN) -- Chelsea crashed to a second successive English Premier League defeat for the first time in four years on Saturday, allowing Manchester United to draw level on points with the leaders.
The defending champions, beaten 3-0 at home by Sunderland last weekend, lost to lowly Birmingham for the first time since the Premier League's inception in 1992 thanks to a rare goal from the home side's veteran midfielder Lee Bowyer.
The 33-year-old, who last found the net almost a year ago, scored against the run of play in the 17th minute after striker Cameron Jerome headed Sebastian Larsson's right-wing cross into his path.
Chelsea surged forward in search of an equalizer, but Ben Foster pulled off a series off superb saves as the goalkeeper bounced back from his uncertain performance in England's 2-1 midweek defeat by France.
The closest the Londoners came to scoring was seven minutes before halftime, when striker Didier Drogba headed against the crossbar.
It was another blow for Chelsea manager Carlo Ancelotti, who lost his assistant Ray Wilkins last week when the former England midfielder's contract was not renewed -- and the Italian revealed on Friday that he had no say in the promotion of scout Michael Emenalo to replace him.
"We played good football, had a lot of chances, but we lost. It is a difficult moment but we don't have to lose confidence," Ancelotti told the club's website.
"I was really disappointed with the performance against Sunderland, but this is different -- just with the result."
Birmingham climbed out of the bottom three, moving up to 12th on 16 points.
Manchester United joined Chelsea on 28 points after 14 matches, beating nine-man Wigan 2-0 as Wayne Rooney made his long-awaited return as a second-half substitute.
The visitors created several chances but France fullback Patrice Evra opened the scoring right on halftime with his first goal in four years, heading home Park Ji Sung's cross.
England striker Rooney came on in the 57th minute before Wigan, who took Birmingham's place in the relegation zone, had captain Antolin Alcaraz sent off for a second yellow card.
Two minutes later striker Hugo Rodallega was sent off for a two-footed challenge on United defender Rafael.
The Brazilian set up United's second goal in the 77th minute with a cross for Mexico striker Javier Hernandez to head home.
Rooney, who angered some United fans by claiming he wanted to leave Old Trafford before changing his mind signing a lucrative new five-year contract, missed two chances to double his meager season's goal tally.
Third-placed Arsenal missed the chance to go top of the table in the early kickoff, blowing a two-goal lead as Tottenham bounced back to win the north London derby 3-2.
France midfielder Samir Nasri poked the ball around goalkeeper Heurelho Gomes and bundled the ball over the line in the eighth minute, then Morocco striker Marouane Chamakh guided Andre Arshavin's low cross into the net on 27.
But Gareth Bale pulled one back five minutes after the interval as recalled striker Jermain Defoe headed on a long ball to Rafael van der Vaart, who cleverly guided the ball on to the young Welsh winger.
Van der Vaart leveled with a 67th-minute penalty after Arsenal captain Cesc Fabregas inexplicably handled his free-kick, and French defender Younes Kaboul glanced home a header from another set-piece by the Dutchman with four minutes left.
It was Tottenham's first win at Arsenal in 17 years, and boosted the club ahead of Wednesday's Champions League clash with Werder Bremen.
"I think Tottenham are now getting closer and the championship is wide open," manager Harry Redknapp told reporters. "Chelsea are not as good as they were; Man United are not as good as they were three or four years ago.
"They're still excellent teams but they're not the force they were. It's wide open for somebody who can put a run together. It's there for someone to have real go at it this year."
Tottenham remained in sixth place on 22 points, on goal difference behind Bolton and Manchester City -- who travel to Fulham on Sunday.
Bolton climbed up to fourth place with a 5-1 thrashing of Newcastle, who had defender Fabricio Coloccini sent off in the 76th minute.
The Argentine was red-carded for a elbow on Sweden striker Johan Elmander, who by that stage had inspired the home team to a 4-1 lead.
Elmander scored twice to take his season tally to eight and was fouled for the free-kick which Matt Taylor fired against the bar, allowing Chung-yong Lee to make it 2-0.
Kevin Davies scored two penalties: the first conceded by former Bolton star Kevin Nolan in the 18th minute and the second at the end to complete the rout after the veteran forward was fouled.
Stoke moved up to eighth place with a third successive victory, winning 3-0 at West Brom.
Winger Matthew Etherington scored a 55th-minute penalty after Kenwyne Jones was fouled, and his replacement Jon Walters converted another spot-kick on 85 and then sealed it in injury-time.
Liverpool bounced back from last week's defeat at Stoke to join their conquerors on 19 points with a 3-0 crushing of bottom side West Ham in the late match.
England fullback Glen Johnson bounced back from criticism from manager Roy Hodgson to chest down a corner and volley in an 18th-minute opener, then Dutch forward Dirk Kuyt doubled the lead from the penalty spot nine minutes later after a double handball from Danny Gabbidon.
West Ham's woeful defending continued when diminutive Argentine winger Maxi Rodriguez was left unmarked to head in the third seven minutes before halftime, prompting a section of disgruntled West Ham fans to head for the exit gates.
The future of the visitors' manager Avram Grant is now in major doubt, with the club's last league win as long ago as September 25 and this latest setback coming after he was publicly backed by his board -- the traditional death-knell for any team boss.
Blackpool rose to 10th place, a point behind Stoke, with a 2-1 victory at home to second-bottom Wolverhampton.
Luke Varney smashed a stunning third-minute volley and fellow striker Marlon Harewood netted from close range just before halftime, while Kevin Doyle's 86th-minute reply set up a tense finish.