Man of the match: Demba ba
The free signing plundered his 15th goal of the season, a superbly executed hooked finish, in what seems certain to be his final appearance for the Magpies before heading off on African Nations Cup duty with Senegal to set United on the way to their first back-to-back league defeats for 10 months.
Frenchman Yohan Cabaye sealed a first victory over Sir Alex Ferguson's men in more than 10 years with a stunning 47th-minute free-kick with Phil Jones' late own goal simply cementing their seventh place in the table.
Even Wayne Rooney's return from his exile could not spark United into life, who rarely threatened, as Newcastle added to the pain inflicted on his side by lowly Blackburn at the weekend in front of a delighted crowd of 52,299.