The Hammers smashed Blackburn Rovers 5-1 in the FA Cup last weekend, and followed that up with a less convincing victory this afternoon.
It was in-form winger Michail Antonio who bagged yet another goal, as he cut in from the right hand side of the box and placed a left footed shot past Vito Mannone and into the corner of the net.
Sunderland did have the ball in the net in the second half, but Jack Rodwell's goal was ruled out for handball, meaning manager Sam Allardyce's return to Upton Park ended in defeat.
West Ham have now leapfrogged Manchester United into fifth place in the Premier League table, and are just four behind fourth placed Manchester City, meaning a push for a Champions League place isn't totally out of the equation.
After the final whistle, former Hammers winger Matthew Etherington took to Twitter to give his verdict on West Ham's performance against Sunderland.
Etherington noted that it wasn't West Ham's finest performance of the season, but that the points were more important than the display - and praised the goal from winger Antonio, who is really making waves at Upton Park having arrived from Nottingham Forest in September.
What did you think of West Ham's display against Sunderland?