Ralf Rangnick says Manchester United's wingers were told to attack Brighton's centre-backs in the second-half in a tactic that resulted in the dismissal of Lewis Dunk.
United led through Cristiano Ronaldo's 51st-minute howitzer and Lewis Dunk was sent off straight from the restart when he was dispossessed by Anthony Elanga and brought the teenager down.
The VAR advised the on-pitch referee Peter Bankes to review his initial decision to yellow card Dunk, who was sent off after Bankes watched a replay on the pitchside monitor.
Elanga started the game on the right-hand side and Jadon Sancho on the left but the pair switched at the start of the second-half and Elanga's pressure on Dunk forced the error.
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