Published: 17:20, 14 January 2017
Dartford had Alex Brown sent off as they bowed out of the FA Trophy.
The midfielder was shown a straight red in first half stoppage-time after a challenge on Chelmsford's Anthony Church, with three other players booked in the scuffles that followed.
Former Kent striker Chris Dickson settled the tie - the third meeting between the sides this season - with the 71st minute winner, touching the ball home at the far post.
Dickson, making his first start after moving from Sutton, got on the end of ex-Darts man Max Cornhill's flick-on, following Robbie Wilmott's corner.
He might have got a second - but wanted one touch too many - with Dartford defender Tom Wynter doing well as the Essex club broke clear.
Earlier Luke Wanadio had two efforts blocked, then set-up Brown for another effort that bounced off a defender in the box.
Duane Ofori-Acheampong had the best chance - denied by a great save from Chelmsford keeper Rob Fitzsimons midway through the first half, and Andy Pugh also had a header saved.
Second half saw Darts make light of being a man short, Fitzsimons cleared Lee Noble's deep cross at the second attempt, and Ofori-Acheampong headed over the bar, before Dickson broke the deadlock as Chelmsford avenged their FA Cup defeat in September - the Essex club's only loss at home this season.
Boss Tony Burman sent on Ryan Hayes and Danny Harris in a double change, with Cornhill missing two chances late on to get a second against his old club.
Darts defender Keaton Wood and Chelmsford pair, skipper Chris Bush and fellow defender Matt Young were booked following the first half handbags, with Ronnie Vint joining them in the second half.
Dartford: Ibrahim, Wood, Vint (Harris (78mins), Bonner, Wynter, Noble, A Brown, Bradbrook, Wanadio (Dembele 89mins), Pugh (Hayes (78mins), Ofori-Acheampong
Subs not used: Habte, Coxall`
Chelmsford City: Fitzsimons, Miller, Bush, Haines, Young, Willmott, Cornhill, Church, Graham (Daley 69mins), Jeffers (Roberts 61mins), Dickson (Rees 90mins)
Subs not used: Porter, Blanchett
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