The goal was deserved reward for the Black Cats, who had recovered from a poor start to the game to dominate Ipswich Town in the latter stages of the game.
They hit the woodwork twice before Maguire’s goal, a strike that lifts them above Paul Lambert's side and back into the play-off places.
A disappointing defeat to Portsmouth had checked Sunderland’s momentum and both sides came into the contest wary of their disappointing records against sides in the upper reaches of the table.
Rotherham’s excellent win away at Lincoln City on Friday night had raised the stakes further still and so it was an understandably tight start to the contest.
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Both sides were going direct at the earliest opportunity and though Sunderland were struggling to get into the contest, they thought they had taken the lead when Chris Maguire played a good early cross from the right into the centre of the box.
Charlie Wyke had a simnple finish but looked well offside and the flag was quickly raised.
That raised the decibel levels inside the Stadium of Light considerably but in truth it was Ipswich Town who quickly began to take control of the contest.
They were showing more composure in midfield and stretching the Black Cats defence.
Will Keane, playing up front alongside James Norwood, was dropping smartly into space in front of the back five and causing a lot of problems.
He went close with Ipswich’s first teal attempt when he headed a cross from Jon Nolan just over the top of the bar.
A good early pass from deep then released Norwood just minutes later, but Jon McLaughlin times his movement of the line well and blocked the initial effort with his chest, allowing the defence to recover and clear.
It was the away side who continued to advance into the final third with alarming regularity, and the Black Cats were fortunate that their opponents were just showing a lack of compousre in the crucial moments.
McLaughlin had to be alert to save from Nolan, while Keane should have done better when the ball broke for him in the box. Bailey Wright blocked his effort well when the best option may well have been to let the ball run for Flynn Downes, the midfielder rushing into the box and sensing an opportunity.
Norwood then missed two good openings, first firing wide from range after an excellent one-two with Keane on the edge of the area, before turning a deep cross from Luke Chambers wide as he ran across his marker.
Sunderland were struggling to make any attacking inroads, George Dobson producing their only real effort give minutes from the break, his left-footed effort from range drifting harmlessly wide.
It had been a very disappointing start to the contest from the Black Cats, but their improvement after the breka was immediate.
Denver Hume, so unusually quiet in the opening exchanges, saw an effort blocked by Janoi Donacien and shortly after that Sunderland came within inches of taking the lead.
Lynden Gooch did superbly to cut in from the right, beating a host of Ipswich players before unleashing an effort that had Tomas Holy comfortably beaten in the Ipswich goal.
The ball struck the post and fell for Wyke, who had to score but could slice his effort straight into Holy’s arms.
Holy then had to make a smart stop from an opportunistic effort from Power as the home side began to turn the screw.
Sunderland were dominant but had a let off when the referee awarded an indirect free kick deep inside their own box. Flanagan had turned the ball towards McLaughlin as he challenged with an Ipswich forward, and it was deemed to be a backpass as McLaughlin picked it up to clear.
Fortunately for the Black Cats, Norwood scuffed his effort and Janoi Donacien could only turn it over the bar at the back post.
Sunderland continued to dominate the contest, and should have scored when Hume again found himself in space on the left. His cross was low and accurate, Bailey Wright somehow turning his effort onto the bar from close range.
The pressure eventually told, however, as Sunderland again broke forward with ten minutes to play.
Between them Wyke and substitute Kyle Lafferty were able to turn the ball into the path of Chris Maguire, who struck a superb effort from the edge of the box past Holy in the Ipswich goal.
Ipswich pushed hard for a winner and though Downes should have done better when he volleyed over from just inside the box, Sunderland defendend well and deserved their win.
Sunderland XI: McLaughlin; O’Nien, Willis, Wright, Flanagan, Hume (Lafferty, 78); Power, Dobson; Maguire, Gooch (McLaughlin, 90), Wyke
Subs: Burge, Ozturk, Watmore, Scowen, Semenyo
Ipswich Town XI: Holy; Donacien (Earl, 77), Chambers, Wilson, Woolfenden, Kenlock; Skuse, Downes, Nolan (Huws, 70); Norwood (Jackson, 70), Keane
Subs: Norris, Judge, Sears, Dozzell
Bookings: O’Nien, 20 Skuse, 23 Chambers, 53 Flanagan, 74
Attendance: 32,726 (1,956 away)