City started the game in lively fashion, but the U’s defended resolutely in those early moments to see away the visitors’ pressure.
The U's had been on top during a fifteen minute, incident packed end to the first half, but that two goal cushion gave the Sky Blues enough to protect in the second period.
Disallowed goals, overturned decisions and goals that were allowed to stand all came up within the course of an eventful ninety minutes in which the visitors ended up 3-1 winners.
The U's fell to a home defeat on Tuesday night in a match full of talking points against Coventry City.
There was little in the way of chances in the first ten minutes, though, with both keepers happy to watch on as the game was played in front of them.
However, Murphy was scrambling across his goal thirteen minutes in when Wordsworth stepped inside from a corner and lashed one only just over the bar.
At the other end, Baker’s dancing feet saw him move across the penalty area, but by the time he got settled enough to take a shot, his effort lacked any real power to test Sullivan.
The U’s keeper was definitely tested on nineteen minutes, with Moussa steaming in at the far post. As the ex-Southend man looked destined to score, Sullivan stood strong to block the ball away.
The home side weren’t firing on all cylinders, but they had another chance as the midway point of the half approached.
A long ball down the channel found Henderson, who got it under control and passed it into the path of the onrushing Wilson.
He took a touch to set himself, and drilled in a low effort that Murphy grabbed at the second time of asking.
The U’s thought they had taken the lead just before the half hour mark when Bean’s deflected shot wrongfooted Murphy and found the net.
There was a long period of deliberation by the linesman on the East Stand side and he eventually ruled it out with visiting players protesting.
The U’s went close again just minutes later, Sears stepping in off the left flank and curling a shot that cannoned off the crossbar with Murphy beaten.
The home side were still left rueing those opportunities when the visitors took the lead with ten minutes going to half time.
McSheffrey was slid in behind Wilson and he took the ball to the byline before cutting it back for Moussa to tuck home.
If the U’s players were angry at their goal being ruled out earlier in the half, they were furious at City getting a second just before the break.
Edjenguele headed home from close range and the linesman’s flag looked like it had immediately ruled the effort.
Yet on this occasion, the referee decided to overrule his linesman to give the goal and give City a cushion going into the break.
With fire still in their belly coming out for the second half, the U’s introduced Massey for Bean as they went all out to get back into the match.
It was the visitors who had the first sight of goal after the interval, though, with McGoldrick embarking on a run at a corner similar to that of Jon Walters for Stoke the night before. His first shot was blocked and he fired his second over.
The U’s were trying their best to get back into the game and two fierce crosses from the right were well defended by the visitors as it looked destined to be smashed home from close range.
City were dangerous on the counter, though, and a McGoldrick shot ten minutes after the break flashed across goal with Sullivan at full stretch.
Morrison was introduced fifteen minutes into the second half, and he was one of three players to be booked in quick succession by the referee Kettle.
From a set piece, the U’s got one back, as Eastman got the deftest of touches to a floated free kick to beat Murphy into his far side netting.
The U’s had their tails up now, but they were coming up against a City side now happy to hit on the counter and keep men behind the ball.
It was with the follow up ball from a set piece that the U’s went close again. The ball found Wilson on the far post, and his diving header was superbly saved by Murphy.
And that save proved crucial when McGoldrick was slotted through late in the game and, with a hint of offside again, he kept his run going to tuck the ball under Sullivan to make it 3-1.
It summed up a frustrating night for the U's, who go again at MK Dons this weekend.