In the other friendly match involving a Premier League team on Wednesday, Tottenham beat Stevenage 2-0 with Gylfi Sigurdsson scoring on his debut.
Despite the game presenting enough chances to finish in a cricket score, Federico Macheda’s calm finish on 19 minutes proved the difference between the sides on Nelson Mandela’s 94th birthday.
As expected, United started the match with much of the possession and created the first clear-cut chance in only the second minute, Macheda finding space to force Tapuwa Kapini into a save that the onrushing Javier Hernandez will have been disappointed not to guide into an empty net.
Further chances followed, Scott Wootton’s touch letting him down with a run on goal beckoning before the hosts nearly stunned United through Ayanda Dlamini, his shot flashing wide of Anders Lindegaard’s right hand post.
But the goal was coming for United and Macheda latched on to a lovely through ball to supply a cool finish past Kapini on 19 minutes.
Amazulu remained dangerous and Dlamini forced Lindegaard into a fine save before hitting a shot just wide moments later. Chicharito spurned two further chances before Amazulu were lucky not to be reduced to 10 men when Carlington Nyadombo clearly pulled back Jesse Lingard when clean through on goal.
From the resultant free-kick Dimitar Berbatov, who started despite publicly wanting an exit from United, found his shot blocked out for a corner, and he then forced an excellent save from Kapini with a fine scissor kick as the hosts ended the half thankful of being just one behind, Macheda firing wide just before the whistle.
The second half developed into a more even contest as the hosts searched for an equaliser, Lindegaard on hand to deny Dlamini straight after the restart. And the impressive Dane had to be on his guard again moments later to tip over the lively striker’s header.
Substitute Tyler Blackett was fortunate not to concede a penalty when he looked to have blocked an Amazulu player off the ball but United finished the stronger, Hernandez doing well not to score in meeting Ryan Tuncliffe’s cross before Davide Petrucci’s late shot cannoned back off the underside of the bar.
Shinji Kagawa got his first taste of action in a United shirt in the dying moments and nearly played in Berbatov with his first touch, but the Japanese star is sure to get plenty of action to shine as the tour continues.
Sigurdsson scored on his Spurs debut as Andre Villas-Boas's side beat Stevenage at Broadhall Way.
Jan Vertonghen played 45 minutes in what was his first appearance in a Spurs shirt, while Tom Huddlestone and Jermaine Jenas, who missed large chunks of last season through injury, took part in Hertfordshire.