The Foxes took the lead in the 63rd minute through Kelechi Iheanacho.
United restored parity just moments later through Fred but could not find the winner they needed.
It was a big game for United, who are currently positioned in 6th and need wins in their bid to finish in the fourth and final Champions League spot.
But, despite the game being of such importance, United were second best for large periods.
And one United fan let their frustration get the better of them after Iheanacho’s opener.
The supporter had some choice words for United’s bench and Darren Fletcher got involved.
Things got heated as they shouted at each other. A video of the incident has emerged and you can view it below…
The supporter, Jamie Caplan, has now spoken to Manchester Evening News where he detailed the exchange.
“I’m not even bothered about the result,” Caplan, 25, said. “At the end of the day, I care about the effort being put in and that was what my argument was about. It was like they didn’t care. The reaction from the bench was they didn’t care. The reaction from the players was that they didn’t care and that’s what I said.
“I said, ‘you don’t f*****g care’. It wasn’t directed at Fletcher personally or anything towards him. He’s the one who took offence and turned around and asked me who the f**k I was and to sit down. That’s when I went back at Fletcher because I took that very personally.
“I then went into a bit of a rage, so he didn’t say much then. And then Scott McTominay turned around. I couldn’t make out what he was saying because I was already walking up the stairs by this point.
“‘Where’s the f*****g fight? You don’t care.’ That’s pretty much word-for-word what I said. He (Fletcher) didn’t like it. But he can’t be in denial, he was there. He knows the standards that are required to be top-level.
“He was in a dressing room with Keane and if he turned around to me and say that’s a good enough United side then he’s a liar and I don’t believe him. Just look at all the old pros, they all say the same thing, it’s just not there, the desire. It isn’t there.
“I wasn’t the only one in the stadium shouting these things at the same time. When Fletcher is saying, ‘who are you?’ He’s not just saying it to me, he’s saying it to all of these people.”
Caplan then walked up the stairs and out of the stadium. He was clapped by some fans but he said he didn’t notice the ovation he was given.
“To be fair, I’d lost it at that point,” he replies when asked if he noticed the applause. “I didn’t know what anybody else was doing. But if they were booing that was the only noise they made all game. I won’t be sitting in the south stand again!”
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Caplan has reiterated his love for the club and will go back to Old Trafford if he’s allowed.
“But I think that’s what the game’s about. It’s about going and venting a bit of frustration. There’s a line – I didn’t overstep any line, I wasn’t personal, so I just see it as a blowout and that’s what football’s about.
“If I’m allowed to go back, I will go back. It’s my club. I love it. I just love being there. I would go back, definitely.
“Sometimes the emotions do get the better of me and probably did a bit on this occasion.
“But I still don’t think I was in the wrong and I’d do it again.”
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