A comfortable victory for Cambridge over a poor Shewsbury side was over-shadowed by an amazing incident in the last minute when two of their players started fighting each other.
Striker Daniel Webb, clearly annoyed that his skipper Luke Guttridge failed to pass to him in front of goal, launched into a confrontation.
The players grabbed each other shirt and an angry bout of pushing and shuffing ended with the referee showing them both yellow cards.
Cambridge had far less trouble from the opposition who went down to their third defeat of the season as they struggled again to make the step up in class from the Conference.
United created nine scoring chances against only a couple a run-of-the-mill free-kicks by the outplayed visitors.
It was highly suprising that the winning goal was a fluke, Shane Tudor's 20 yard volley hitting fellow striker Daniel Chillingworth and looping over helpless keeper Scott Howie.
Webb hit the cross bar and Chillingworth forced an excellent save from Howie as Shrewsbury surrendered in the last ten minutes.
Their cause was hardly helped by the controversial red card for Jamie Tolley in the 81st minute after a great scruffle with Guttridge.
The only threat from Shrewsbury was a Luke Rodgers' free-kick on the half hour which was struck straight at teenage goalkeeper John Ruddy.