Four goals from Iyseden Christie hauled Mansfield off the bottom of the table and ended Colchester's four-match unbeaten run.
Yet Christie almost missed the game after being held up in traffic and only arriving at the ground 15 minutes before the kick-off.
Christie showed no ill effects from his mad dash however as he smashed a ten-minute hat- trick in a crazy spell of five goals in 13 first-half minutes.
Then with the relegation battle in the balance he struck his killer fourth goal, racing clear onto Craig Disley's 63rd minute pass and slotting into an empty net moments after Stags defender Jamie Clarke had cleared Bobby Bowry's shot off the line at the other end.
Any hopes of a Colchester recovery were finally ended nine minutes from time when defender Alan White was sent off for one of numerous fouls on Christie.
Mansfield had waited 301 minutes for a home goal when Christie struck the first of his treble, glancing in Disley's 19th minute piledriver.
Five minutes later the UÂ’s were level when Joe Keith converted a penalty after Neil Moore had pushed Scott McGleish.
Within 40 seconds however Christie restored Mansfield's lead with a looping header on the end of substitute Neil Mackenzie's long pass.
Kevin Rapley's raking 25-yard drive was tipped onto the bar by the flying Kevin Pilkington as United pressed for a quick second equaliser.
But just 20 seconds later Christie completed his treble turning in Mackenzie's corner.
However Kem Izzet's incisive throughball handed the visitors a lifeline 13 minutes before the break as Rapley raced clear to score