Ipswich Town were condemned to a third straight home defeat and fall to 10th in Sky Bet League One, as Charlie Wyke netted his 12th league goal to move the Black Cats within one point of the play-offs.
The frontman's goal on the stroke of half-time was enough to see Sunderland record an impressive victory and climb to seventh at the expense of an Ipswich side who have now lost their past three matches at Portman Road.
Story of the match
Grant Leadbitter's curling delivery for the Black Cats was cleared comfortably by the hosts, to prevent any danger from a free-kick following a tussle on the wide right on Wyke.
Ipswich were reduced to 10-men inside the first 10 minutes when striker Kayden Jackson rose his boot high down the leg of Sunderland defender - Bailey Wright.
Just after the quarter-hour mark, the Tractor Boys had a free-kick of their own but visiting stopper Lee Bulge comfortably claimed Mark McGuinesses' header after rising to meet Andre Dozzell's set-piece delivery.
Wyke has been in fine goal-scoring form of late, netting four goals in three League One matches. He will have sensed the net could bulge once more when the ball fell to him in close range of goal, however, Tomas Holy did well to save the snapshot and keep the score level.
Late first-half drama ensued when Ipswich went close at one end via Gwion Edwards as the Wales international cut inside from the right, but he drove his shot into the side netting.
Just moments later, Sunderland were clinical at the opposing end and broke the deficit. Black Cats captain Max Power delivered a perfectly weighted ball for Wyke, who pounced first time onto the cross, and stabbed home past Holy - for his 12th goal of the campaign thus far.
After notching themselves in front before the interval, Sunderland were the side that came out the hungriest at the beginning of the second-half.
Leadbitter's corner swooped into the area and Black Cats defender Jordan Willis, but he could only guide his effort straight into the hands of Holy.
Substitute Elliot Emberton was just inches away from doubling the visitors lead, as his deflected strike dipped just wide of the upright.
The hosts' first notable chance of the second-half came through Barnsley loanee Luke Thomas, when he shuffled the ball onto his left foot and fired towards goal. Bulge was equal to the opportunity and Dozzell was unable to capitalise on the rebound.
On the hour-mark, Paul Lambert's men had McGuiness to thank when he crucially denied Aiden O'Brien's effort on the line and prevent the Black Cats from doubling their lead.
The game petered out and the tempo slowed as Sunderland defended well to see out an important three points and prevent Ipswich from re-railing a play-off charge, after an inconsistent spell.
Wyke continues rich vein of form
Sunderland's upturn of form is too great credit of Wyke, who added yet another goal to his impressive tally for the season.
His clinical finishing will go a long way to helping the Black Cats in their promotion fight back to the second tier this campaign.
Lee Johnson's men have now kept an impressive three clean sheets from their last four league outings. Despite being the stronger side on the night - seeing more of the ball, they were resolute and defended strongly once more, when called upon via Ipswich attacks.
Portman Road woes continue
Making the home ground a fortress is something that the fans love and everyone on the playing side of the game wants to do, however, the Tractor Boys have now lost three consecutive home matches and it's a second successive one without scoring.