Dikgacoi caught Ashley Young as the winger surged towards goal, with the challenge resulting in a penalty for United and Dikgacoi red-carded due to being the last man between Young and the goal.
The match ended 2-0 in United's favour, but the red card proved to be the turning point. Speaking after the match David Moyes adjudged the decision to be fairly harsh and condemned Ashley Young's apparent dive.
“The boy (Dikgacoi) definitely throws his leg out, but I think Ashley has put his leg into his leg. It is not what I want,” Moyes said.
“I don't like the rule where every time it is the last man it means it is (a red card). I thought it was harsh. If I was Ian Holloway [Crystal Palace manager] I would be disappointed.
“OK, it might be a penalty. But I don't think the boy made a challenge to wipe him out. Unfortunately that is the rule.”
Ian Holloway remained tight-lipped about the decision due to a recent touchline ban and hefty fine after his public criticism of officials following Palace's loss to Tottenham Hotspur.
“My opinion doesn't count and I've just got to deal with it,” said Holloway after the match.
“I literally can't afford it, let everyone else judge what they think. I want to keep my money in my pocket and pay for my other daughter's wedding next summer!”
Dikgacoi is not a stranger to being shown red cards in the Premier League. After joining Fulham 2009, Dikgacoi was shown a red card after being on the pitch for 42 minutes. It was his club debut for the Cottagers, but Dikgacoi struggled to break into the side after such an acromonious start.
The sturdy defensive midfielder earned nine yellow card last season for Crystal Palace, which took his tally to 17 yellows since moving to England.
The straight red will mean that Dikgacoi should be banned for the next three games for Palace, who will need to find a suitable replacement in midfield.