Sir Matt Busby's side triumphed 2-0 in the first leg in Brussels but were still anticipating a tough road to the next round of the 1956 European Cup, the first time an English team had entered the competition.
Dennis Viollet led the way with four of the goals and Tommy Taylor also bagged a hat-trick. Liam Whelan (2) and Johnny Berry added their names to the scoresheet but David Pegg also deserves a mention after setting up many of the 10 goals.
"We were all keyed up for the return match and also a little anxious because we too were playing away from home," said Busby.
"We had to stage the tie at Maine Road because Old Trafford did not then have floodlighting. The conditions were also a little unsettling. It had rained heavily and the pitch was covered in pools of water. We needn't have worried though. The boys won 10-0, an incredible score which possibly had some people assuming that Anderlecht were a poor side.
European Cup preliminary round 2nd leg
26.09.56, Maine Road
(Viollet 4, Taylor 3, Whelan 2, Berry)
United: Wood, Foulkes, Byrne, Colman, Jones, Edwards, Berry, Whelan, Taylor, Viollet (pictured), Pegg.