With the Shrimpers playing Newcastle United the night before, the Clarets welcomed Kevin Maher back to Melbourne Community Stadium as he brought along the Club's u21 side.
The youthful Blues started the friendly well winning a couple of corners early on which came to nothing, but it was the Clarets who created the first opening in front of goal when Bagasan Graham and Billy Bricknell linked well before Bricknell skied his strike on goal.
Graham was causing a constant nuisance on the left hand side and he drilled a low cross into the near post towards City's Tralist, whose flick on goal was blocked away for a corner.
Whilst Graham was proving troublesome on the left, Robbie Willmott carved out the Clarets' best opening of the game thus far from the right, when his free kick was headed over from close range by Anthony Church.
Willmott again produced a perfectly flighted cross into the area five minutes before the half time interval which was headed on target by the Trialist, but the Southend 'keeper done well to get down and stop the ball creeping in at the far post.
Chelmsford then made it a hat-trick of missed heading opportunities as Mark Haines missed the best of the lot right before the break, heading over from eight yards out when he was unmarked and onside.
The Clarets continued to put the pressure on in the second half and struck the woodwork through Bricknell, but it was the visitors who took the lead against the run of play. Southend took a quick free kick following a scuffle involving Graham which ended up with the ball being tapped in at the far post by Harry Phillips.
The response from Rod Stringer's side though was perfect as within four minutes the Clarets were level. Chris Bush outmuscled the Southend right back to get free down the left before picking out the head of Bricknell who powered the ball home at the far post.
With the match level City went for the winner and Haines again had a golden chance go begging as his header inside the area went wide. But his miss was all but forgotten seconds later when a cross from the right was met by the head of Reid who guided his header into the top corner.
Chelmsford had the chance to wrap up the win late on, on the counter attack, when Willmott sprinted away, playing in Shamir Mullings who was denied by the feet of the Southend stopper. It wasn't to matter though as the Clarets made it five wins from six pre-season games so far.
Their final match before the start of the season takes place on Saturday as they entertain National League Premier side Dover Athletic on what will be the Club's Family Fun Day. More details about the Fun Day are available on our events page.