Manchester United opened up a three-point lead at the top of the Premier League after cruising past lowly Bolton Wanderers 2-0 on Wednesday.
The prolific Cristiano Ronaldo inspired the re-shuffled Reds to a fourth consecutive league victory with two classy first-half goals to take his tally for the season to 33.
In a rip-roaring London derby at White Hart Lane, Chelsea led three times against Tottenham Hotspur but were held 4-4. Joe Cole's double looked to have earned Chelsea the points before Robbie Keane struck a superb 88th-minute equaliser.
Victory would have put Chelsea level on points with Arsenal but they still trail the Gunners by two points and champions United by five in a thrilling title race.
"It was a good game for the supporters but not for us because we wanted to win and we haven't done it," Chelsea manager Avram Grant told reporters.
"But we are still in the title race and we will continue fighting."
Ronaldo was captain for the night at Old Trafford and the Portuguese winger repaid manager Alex Ferguson's tribute with a masterful display to see off struggling Bolton.
With several first-teamers, including Wayne Rooney, rested Ronaldo took charge. He crashed in his first after nine minutes following a corner and adding yet another swerving free kick to his dazzling collection to make the game safe by halftime.
He has now surpassed the 32 goals scored by George Best in the 1967-68 season, the highest season's tally for a United winger.
"It's a lead, that's important. It's not a significant lead, but it's a lead nonetheless," United manager Alex Ferguson told Sky Sports.
"I think Chelsea hold the key, they have ourselves and Arsenal at home, and their home record is very good, so that to my mind is going to make it a really tight finish."
KICKING THEMSELVES
Chelsea were left kicking themselves after squandering two points at Spurs, having led 3-1 with 15 minutes to go.
Didier Drogba gave the Blues the lead with a third-minute header only for defender Jonathan Woodgate, who scored the goal that gave Tottenham a memorable League Cup victory over Chelsea last month, to equalise after 10 minutes.
Michael Essien restored Chelsea's lead after being played in by Cole and Cole made it 3-1 after 52 minutes when he shrugged off a weak challenge by Pascal Chimbonda.
Dimitar Berbatov headed Spurs back into contention and substitute Tom Huddlestone made it 3-3 with a thumping shot through a crowd.
Cole pounced again to shoot high past keeper Paul Robinson but in a barnstorming finish Keane curled an unstoppable shot past Carlo Cudicini. Berbatov almost won it for Spurs in stoppage time but Cudicini somehow parried his close-range shot.
