An Ollie Palmer penalty saw Lincoln claim a 2-1 win in a feisty encounter at Stevenage.
Matt Godden opened the scoring in the first half before Lincoln's Matt Green picked up a second yellow card for dissent early in the second period.
Despite being a man down, Sean Raggett equalised for the visitors from a corner before Palmer turned the game on its head with a calm penalty on 75 minutes.
Stevenage's Luke Wilkinson received a straight red for a stamp on Alex Woodyard as the hosts were unable to find an equaliser.
After some forgettable opening exchanges, the match burst in to life with Godden's goal, which saw him drive an effort into the corner of the net.
Stevenage's lead nearly doubled moments later after Harry Beautyman's header hit the post, before Godden's effort was cleared off the line by Luke Waterfall.
After Green's dismissal, the Imps were level when an unmarked Raggett nodded in Billy Knott's corner.
And the away side were not to be denied and on 75 minutes, they were awarded a penalty for a Chris Welpdale handball and substitute Palmer converted.