With a starting line-up containing three debutants, Sutton United turned in a fine performance at the Melbourne stadium to inflict Chelmsford's first defeat under new manager Mark Hawkes.
A 2-0 win in Essex, thanks to goals from Jamie Slabber and Dale Binns, lifted United to third in the Skrill South table, Lining up under boss Paul Doswell for the first time were goalkeeper David Gregory and defenders Alex Wynter and Rhys Weston.
Up front, Jamie Taylor was reunited with Slabber, and the partnership caused persistent problems to the home defence with Slabber, returning to his former club, setting United on the way to victory with a fine diving header.
Chelmsford carried an early threat down the left through Aaron Greene and Leon Redwood, the latter having played a handful of games pre-season in Sutton colours.
From one Redwood cross, Luke Callender, with three goals in three games for Chelmsford since following his manager from Heybridge, flashed a header just over the bar.
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As the half progressed, though, United looked to carry the greater threat and they nearly went ahead when Lee Sawyer's deep corner was tipped away by goalkeeper Carl Pentney, but met by a thumping angled half volley from Charlie Clough which rebounded across goal off the face of the crossbar.
United went close again six minutes before the interval when Slabber produced a superb run down the right, surging past two covering defenders before pulling the ball back for Sawyer, who turned the ball goalwards.
However, it lacked the power to cross the line before Sam Long recovered to make a brilliant goal-line clearance.
Taylor also shot across goal when he might have done better after Craig Dundas had headed on a long Gregory clearance, and with the last kick of the half Sawyer's free kick was saved by Pentney.
Having been second best as the half progressed, Chelmsford came out strongly after the break and fashioned their best chance 11 minutes in when Callander was put through on the right.
Under pressure from Clough, he still got in a low shot which Gregory did well to push away just out of the reach of the onrushing Greene, and although the ball eventually fell to Redwood on the edge of the penalty area Gregory was again well placed to save low to his right.
A minute later, United made a double substitution, Weston and Kane Haysman making way for Mitchell Nelson and Damian Scannell, and Binns moving in to a more attacking role, and within six minutes the switch had paid dividends.
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Binns shrugged off an untidy challenge from Long and sent in an inviting cross that was met by Slabber's diving header which flew in to the top corner of the net.
The otherwise impressive Harry Osborne picked up his third booking in as many games soon afterwards for a foul on Greene, but despite a lot of effort Chelmsford found it impossible to make too much of an impression on a solid United defence.
It was not until four minutes from time, however, just after Dammy Shitta had become the fourth debutant of the afternoon, that United finally secured the points thanks to Binns finally opening his account for the season.
United: Travelling fans celebrate the opening goal with Jamie Taylor and Jamie Slabber
It was a slightly bizarre goal as Binns would have anticipated being more the provider when he collected Sawyer's short corner and crossed low from the by-line.
However, a miscued clearance flew so high in the air that, by the time Pentney had clawed the ball out of the six-yard box, Binns was in a much more central position and ideally placed to shoot past the two defenders covering on the line.
United host Weston-super-Mare this weekend.
Sutton: D Gregory, H Osborne, D Binns, A Wynter, C Clough, R Weston (sub M Nelson 57), K Haysman(sub D Scannell 57), C Dundas, J Slabber(sub D Shitta 86), J Taylor, L Sawyer.
Subs not used: P Telfer, T Lovelock.
Highlights from Sutton United's win over Chelmsford SUFCTV