Noah Chilvers bagged a brace as a dominant second-half performance saw Colchester come from behind to secure a 3-1 victory at 10-man Scunthorpe.
The bottom-of-the-table Iron had gone in front courtesy of Joe Nuttall's close-range finish in the 11th minute, and were good value for their lead.
But the game turned following home full-back Luke Matheson's sending-off 10 minutes before half-time for a second yellow card, with the Us given a much-needed confidence boost.
The visitors dominated after the break and drew level when Chilvers charged three-quarters of the length of the field and found the far corner in the 61st minute.
Six minutes later and the Us were in front, with goalkeeper Rory Watson - who had earlier denied Chilvers, Brendan Sarpong-Wiredu and Freddie Sears - helpless as Owura Edwards slotted home following a clever one-two.
Although in complete control, Chilvers headed in a third Colchester goal to make the points safe with 76 minutes gone after Watson had again done well to save from Sears.
Scunthorpe hit both the bar and the foot of a post in a late spell of pressure but never looked like stopping the visitors from making it back-to-back league wins for the first time this season and putting further daylight between themselves and the relegation zone.