Sir Alex Ferguson's men go into Wednesday's friendly against Juventus still unbeaten in pre-season, despite a decent test against a Peterborough side managed by his son Darren.
Darron Gibson's glorious second-half strike, added to a first-half owngoal by Peterborough right-back Russell Martin, saw United win their first away match on English soil since that momentous May day in Wigan.
Irish midfielder Gibson had been on the field for less than a minute as United's eighth and final substitute when he brought down Lee Martin's flicked pass with his right foot and crashed home an unstoppable half-volley with his left boot from 30 yards out.
That wonderful moment in the 68th minute brought a big grin to the face of Sir Alex but there was plenty for the Reds boss to smile about throughout the evening, not least the first appearances of his new full-backs, Brazilian twins Rafael and Fabio Da Silva.
Rafael played the full 90 minutes at right-back and was joined in the team for the second half by brother Fabio at left-back. United finished the match with three Brazilians on the London Road pitch, following Rodrigo Possebon's entrance just before the hour.
The Reds made numerous changes at half-time, having taken the lead a few minutes earlier when Russell Martin, otherwise impressive on his home debut for Peterborough, chested David Gray's right-wing cross past his own keeper Joe Lewis. Nani and the lively Carlos Tevez were both involved in the build-up with the latter eventually feeding Gray.
With Gray backed up and sometimes overlapped by Rafael Da Silva, Peterborough had to deal with a number of raids down their left side. Not that it was much quieter for Posh on the other flank with Nani and Reds left-back Patrice Evra stretching their legs on a