Ian Holloway blasted the boo-boys after his stuttering Swindon side blew a chance to pull clear at the top after eking out a drab draw with Colchester.
The Robins are just behind leaders Walsall on goal difference after failing to win in three games.
Sub Ollie Palmer went closest for Town when his volley grazed the outside of the post before Samson Tovide’s diving header flew narrowly wide in injury time.
Holloway said about the reaction of frustrated fans: “This can’t right – I saw everybody trying hard, so why are they booed off?
“It is bitterly disappointing for me. I don’t feel that we were all together today.
“If my players don’t try, you can boo ’em. If they try as hard as they can, and it don’t come off, I don’t think you should boo ’em and you’ll be arguing with me over that.
“I swear to you, I didn’t see anybody out there not trying.
“It’s days like this that might get you promoted, and days like this we should stick together and say, ‘Well done, lads and be clapped off’, instead of my lads having to clap you lot when you’re moaning at ‘em.
“They are gutted in there. Maybe it is what it is now but it sickens me.”
While the home side’s stars showed plenty of individual skill they rarely strung together anything of note to threaten the United goal.
Palmer’s volley seemed likely to break the stalemate but struck the upright late on.
In added time former Town full-back Ellis Iandolo flashed in a perfect cross but U’s sub Tovide’s diving header missed the target.
U’s boss Danny Cowley said: “We’re just super frustrated that we haven’t won the game.
“I thought in the first half, we created so many chances at will, really.
“I was really pleased with how we played in the first half.
“And yeah, in the second half, I thought it was more even. They have a good chance where Ollie Palmer hits the outside of the post.
“We obviously have a really good chance. Brilliant cross from Ellis, Samson just couldn’t get it between the post, but that was great to get the first contact.
“And yeah, my feeling is that at 70 minutes, that game was there for the taking,
“And when we become a good team, because we’re still growing. Then I think we will find it in ourselves and find the levels to turn and screw and come away with a win.
“Because I thought we deserved it.”
