The Clarets arrived in the West off the back of ten games unbeaten, but Rod Stringer’s promotion chasers were beaten by their League topping counterparts.
Connor Lemonheigh-Evans opened the scoring for the hosts before Lamar Reynolds levelled the tie with his first goal for the Clarets.
Goalkeeper Harry Wright produced an excellent fingertip save to deny Reid from the penalty spot, but the League top-scorer made no mistake on the hour-mark as he restored his side’s advantage.
City continued to press for an equaliser, but their attacking desire left Jake Andrews free to score with a pinpoint diving header.
Chelmsford boss Stringer made one change to the side that beat Oxford City 2-1 on Saturday; Rhys Murphy dropped to the bench as Lamar Reynolds was given a start at Plainmoor.
And the squad rotation almost heaped reward in the second minute when the tricky forward delivered a low cross towards Chris Whelpdale, but the winger was unable to get a shot on-target as his effort dragged harmlessly wide.
Gary Johnson’s side eventually settled into the game and began to test the Chelmsford at a greater frequency. Ruari Keating forced Wright into a smart save from close range within the opening ten minutes; Asa Hall also directed a header wide from Liam Davis’ pin-point cross.
City had a great chance to lead when Reynolds clipped the bar after good link-up play from Whelpdale and Fenwick, but the visitors were made to pay for their hesitancy when Lemonheigh-Evans avoided the Chelmsford challenges and shot well past Wright to open the scoring.
The Clarets responded excellently though and waited just seven minutes before replying to the opening goal. Billy Knott’s excellent pass forward split the home defence, allowing Reynolds to dart through where he executed a sublime chip over Shaun MacDonald in the Seagulls’ net.
Either side tested each other’s opposite numbers shortly after. Both teams looked to assert some dominance, but Wraight’s arrowed effort flew narrowly wide before Lemonheigh-Evans ballooned an effort over the crossbar.
Hall’s header almost restored the Seagulls’ leader shortly before the break, but the scoreline was level when the whistle was blown for half-time.
The hosts burst out the blocks at the start of the second half and were handed a glorious chance to score early on when awarded a penalty; however, City’s on-loan shot-stopper produced a sublime save to tip Reid’s penalty around the post.
Johnson’s words at half-time clearly energised the hosts as they dominated the opening stages of the second half, and it did not take long before they restored their lead. Keating’s clever movement allowed him to find space to pull-back to Reid who stroked home from close range.
Jake Andrews almost doubled the home side’s advantage three minutes later, but his fierce shot flew marginally wide.
Tom Wraight and Fenwick linked up well on 68 minutes, allowing the former to shoot towards goal – it was a comfortable save for MacDonald.
Lemonheigh-Evans threatened Wright again as he produced a low fizzing effort, City’s young shot-stopper dealt with it well.
The Clarets were unable to deny the hosts a third goal, however, when Andrews met with Keating’s cross to direct the ball beyond Wright with twelve minutes left.
Chez Isaac tested MacDonald’s reactions late on with a long-distance strike, but his effort flew narrowly over as City were made to return home with nothing to show for their efforts.