London: Chelsea opened 2015 by seeing its English Premier League lead wiped out by a frenzied 5-3 capitulation to Tottenham on Thursday as former midfielder Frank Lampard drew Manchester City level on points with a 3-2 victory over Sunderland.
Uncharacteristic defensive frailties by Chelsea allowed Tottenham to beat its London rival for the first time in almost five years, with Harry Kane scoring twice.
Never before, across Jose Mourinho's two spells as manager, had Chelsea conceded so many times.
"We made some defensive mistakes," Mourinho said. "We had some individual problems with the defensive structure."
As did Man City, but the champions recovered after squandering a two-goal lead for the second time in a week, preventing a repeat of the 2-2 draw against Burnley on Sunday.
It showed just how important it was for City late on New Year's Eve to secure the 36-year-old Lampard until the end of the Premier League season rather than see him return to sister club New York City FC to start the Major League Soccer campaign in March.
With Chelsea and Man City level on points, goal difference and goals scored, only alphabetical order keeps Chelsea on top.