Aiden McGeady and Max Power's late strikes for Sunderland secured a 3-1 win over 10-man Oxford as the Black Cats kept the heat on in the race for automatic promotion from Sky Bet League One.
A hotly-contested game saw U's boss Karl Robinson sent to the stands after McGeady's 81st-minute goal, with Oxford midfielder Mark Sykes having earlier been dismissed for a second yellow card just after the hour.
But Sunderland, who stay third, made the most of those incidents by coming from behind to extend their unbeaten run to 13 matches in all competitions.
The high-flying hosts did not have it all of their own way and they faced a harder challenge when James Henry's brilliant strike put Oxford in front in the 21st minute.
Henry struck first time inside Lee Burge's far corner after Brandon Barker's excellent run and pass deep inside the home side's half created the opening from 22 yards.
But Lynden Gooch's near-post finish following Jordan Jones' clever run and low cross in the second minute of first-half stoppage-time levelled things up.
After the restart Oxford had Sykes sent off just after the hour for a second caution when he was late on Luke O'Nien in the Sunderland area.
Jones then hammered the Oxford bar with a long-range drive soon after, but Sunderland were not to be denied and, with nine minutes remaining, McGeady was on hand to drill low inside Jack Stevens' bottom corner from the edge of the area after Gooch's run inside.
Oxford pressed in the closing stages but Sunderland wrapped things up when Power was left with just the keeper to beat deep into stoppage time.