It was a nightmare start for Lewis Young's men as goals from Alistair Smith and Richie Bennett gave the home side an early 2-0 lead before Smith got his second four minutes from time to finish of the win for the play-off hopefuls.
Here are the player ratings from the Reds fans who travelled to Sutton. Reds final home game is Saturday where they face Leyton Orient.
See also 'I feel like I probably prepared the team wrong' - Crawley Town's Lewis Young takes responsibility for Sutton United defeat
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1. Glenn Morris 7
Glenn Morris 7
2. Jordan Tunnicliffe 7
Jordan Tunnicliffe 7
3. Tony Craig 6
Tony Craig 6
4. Joel Lynch 7
Joel Lynch 7