The Black Cats took an early lead when Ross Stewart was brought down by U’s defender Lloyd Jones, who was subsequently sent off.
Stewart then converted from the penalty spot before Elliot Embleton doubled the hosts’ advantage with a free-kick.
Cambridge pulled a goal back through Paul Digby, before Stewart added his second, while Nathan Broadhead and Danny Batth also got on the scoresheet.
Kyril Louis-Dreyfus and Juan Sartori were at the Stadium of Light for the clash – here, we take a look at the best photos of throughout the afternoon:
. A win for Sunderland
Watching the match at the Stadium of Light Photo: Frank Reid
. Supporting the lads
Sunderland fans in action on Wearside Photo: Frank Reid
. Taking in the scenes
Sunderland are chasing a play-off spot Photo: Frank Reid
1. Supporting the lads
Sunderland fans in action on Wearside Photo: Frank Reid
2. Taking in the scenes
Sunderland are chasing a play-off spot Photo: Frank Reid
3. Sunderland fans
Sunderland are up to fourth in League One after the win Photo: Frank Reid
4. Shareholders at the SoL
Juan Sartori was pictured with Kyril Louis-Dreyfus Photo: Frank Reid