Van Gaal was left stunned by a shambolic defensive performance from his reconstructed team and admitted it brought back painful memories.
Man United were looking good to achieve back-to-back wins in the Premier League for the first time under Louis van Gaal when leading 3-1 thanks to goals from Robin van Persie, Angel Di Maria and Ander Herrera.
However, the newly-promoted side hit back with devastating effect in the second half of the match.
Goals from David Nugent, Esteban Cambiasso, Jamie Vardy and Leonardo Ulloa saw Nigel Pearson’s men fight back from 2-0 and 3-1 down to win 5-3 and pick up their first win at the King Power Stadium in the Premier League.
After two home draws against Everton and Arsenal, the Foxes were looking for a big result against a rejuvenated Man Utd side who started with Falcao, Van Persie and Wayne Rooney in attack.
Reports say Manchester United manager, Louis van Gaal, gave his squad the famous Sir Alex Ferguson hairdryer treatment following the humiliating 5-3 loss.
This is according to Sky News anchor, Eamonn Holmes, who said he walked past the United dressing room after full-time and revealed that Van Gaal handed a stern dressing down.