Oli Hawkins' first league goal of the season was not enough for Mansfield as they left VBS Community Stadium empty handed for a second successive season.
Sutton proved to be Stags' bogey team last season – the only team to beat them twice – and continued their success against Mansfield with a 2-1 win this afternoon.
The hosts ultimately showed their lethal touch in front of goal in a contest of equal opportunities, reflected in the match stats; both sides having only three shots on target.
Boss Nigel Clough made three changes to the starting lineup following last Saturday's impressive 2-1 win at home to Stockport County.
Lucas Akins and Stephen Quinn returned to right wing-back and midfield, respectively, while Oli Hawkins started in attack for the first time this season.
Jordan Bowery was ill, though expected to return for Tuesday's Papa Johns Trophy group match on Tuesday at home to Manchester City under-21s, while midfielders George Maris and Ollie Clarke were moved to the subs' bench.
Mansfield goalkeeper Christy Pym was called upon as early as the fifth minute when Donovan Wilson peeled away from the defence following a neat throughball, but Pym stood well to deny the frontman with his legs.
Hawkins earned Stags' first corner when he robbed Louis John of the ball on the right hand flank before shooting against a Sutton defender, though Quinn's flag kick came to nothing.
With quarter-of-an-hour gone, Hawkins linked up brilliantly with Swan to feed the Nottingham Forest loanee towards the area. And his run into the box was only halted by a cynical foul from Coby Rowe, who received a yellow card after pulling the forward to the ground.
Stephen McLaughlin then stepped up from 19 yards to whip a left-footed free-kick off target.
Four minutes later, Josh Neufville fired wide from the edge of the box following intricate play inside the Stags' box.
Rob Milsom delivered a dangerous swinging corner in the 26th minute, which flew to the back post for Harry Beautyman, who, under pressure from George Lapslie, directed a close-range effort against the back post.
John-Joe O'Toole entered the referee's notepad for bringing down Randall on the touchline,
On 36 minutes, Riley Harbottle made a vital last-ditch sliding intervention on the cusp of the Stags' goal area to stop Craig Eastman after the Sutton captained danced his way into the box.
With little separating the two sides, United found the breakthrough a minute before the end of normal time at the end of the first half.
Neufville turned the jets on and powered his way through the middle of the Stags' defence before rifling low into the bottom left hand corner.
Five minutes into the second-half, Swan struck into the back of a defender following a good knock down by Hawkins inside the box.
On 52 minutes, Hawkins was in the thick of the action again and almost gave Stags a leveller.
Hartigan's superb corner flashed across the six-yard box, and almost unknowingly, Hawkins headed on to the roof of the net from close range.
Stags maintained heavy pressure on the home goal and McLaughlin went close with a bended effort following Swan's pull back from the goal-line.
On 58 minutes, Riley Harbottle made way for Elliott Hewitt in Stags' first change.
Eastman turned the ball over his own bar from Lucas Akins' right sided cross as Mansfield's corner count began to mount.
John-Joe O'Toole was replaced by Kieran Wallace before Quinn was shown a yellow card for a late tackle on Beautyman
Stags made a treble change as George Boateng, George Maris and Kellan Gordon replaced Hartigan, Quinn and Akins.
Moments after the substitutions, Stags were level with 75 minutes on the watch.
McLaughlin swept in a pin-point free-kick from the left and Hawkins rose highest inside the box to direct a bullet header beyond Sutton goalkeeper Jack Rose.
Sutton brought on three fresh faces on 80 minutes and, within two minutes, were back in front.
Stags were unable to defend a deep ball into the box and Tope Fadahunsi was allowed to knock the ball home inside a crowded area with his first touch of the game.
Sutton, characteristically on home soil, kept Stags out in the remaining stages as Mansfield continue their search for a first away victory of the season, in stark contrast to their home form.
SUTTON: Rose, Milsom, John, Rowe, Kizzi, Randall (Smith 84), Beautyman, Eastmond, Neufville (Boldewijn 80), Wilson (Fadahunsi 80), Thomas (Kouassi 80)
UNUSED SUBS: House, Gambin, Barden
STAGS: Pym, Akins (Gordon 74), O'Toole (Wallace 65), Perch, Harbottle (Hewitt 56), McLaughlin, Lapslie, Hartigan (Boateng 74), Quinn (Maris 74), Hawkins, Swan
UNUSED SUBS: Flinders, Clarke
ATTENDANCE: 2,664 (372 Stags' fans)
REFEREE: Lee Swabey