The first goalmouth action came in the 13th minute when the visiting Red Devils had a goal disallowed. Marouane Fellaini was the man who found the net, but it was ruled out because of a handball offence.
Minutes later manager David Moyes had to make an early substitution when Ashley Young was forced off because of an apparent dislocated finger, with Adnan Januzaj coming on in place of the Englishman.
Newcastle's closest efforts in the opening period came from Papiss Cisse, who twice tested Anders Lindegaard in quick succession midway through the half.
The visitors took the lead in the 38th minute when Juan Mata scored for the second straight game by curling a 20-yard free kick into the top corner.