Marvin McCootie gave the visitors the lead against the run-of-play on 13 minutes, seeing his initial shot saved before the ball smashed into his shin and beyond Ross Fitzsimons.
Chelmsford defender Michael Spillane scored his second goal in as many games in the 42nd minute, capitalising on a defensive mistake to equalise before the break.
Axel Andresson’s own-goal on the hour-mark put the home side ahead, directing Louie Theophanous’ wayward shot into the goal.
The City striker furthered the hosts’ lead after rounding Max O’Leary, before the Clarets were reduced to ten-men following a late tackle from Spillane.
The home side held much of the possession in the opening encounters, but the physicality of Bath’s Marvin Morgan proved a problem to handle.
Chelmsford came close when Theophanous controlled well on the by-line, but his drilled cross was cleared away by Chas Hemmings.
Shaun Jeffers provided an engine for the Clarets up-front, chasing down every ball that went in his direction, and his determination created the reward as he won a corner. However, the corner was headed out to Daley, who returned the pass to Jeffers who dragged his shot wide.
Bath almost doubled their advantage just before 20 minutes but an incredible one-handed save from Ross Fitzsimons denied Morgan’s free-header.
Robbie Willmott became the first City player to enter the book as Church impeded a Bath player, but the winger kicked the ball away and was penalised for his actions.
The Clarets came close to equalising on 33 minutes when Luke Daley fizzed a cross into the box, but the delivery evaded the runs of Chris Dickson, Louie Theophanous and Jeffers.
Willmott continued his form by causing trouble with his in-swinging crosses, but neither Chris Dickson nor Josh Hill could score – with the latter having his header cleared off the line.
The home side eventually converted one of their chances, three minutes before the half-time interval. Michael Spillane read a defensive error, took advantage of it and sent the Romans’ keeper the wrong way with an instinctive striker’s finish.
The Clarets took the lead for the first time in the afternoon as Theophanous’ wayward shot was diverted in by Skipper Andresson beyond his own goalkeeper on 59 minutes.
The visitors almost restored parity when a cross from the right wing smacked against the post, but Fitzsimons quickly brought an end to the danger.
But City extended their lead with fifteen minutes remaining. The Clarets broke with the ball seconds after the visitors had a penalty claim, and Theophanous rounded ‘keeper O’Leary before firing high into the goal.
The hosts already had a firm grasp on the three points but the task was made marginally more difficult when Spillane was given his marching orders. The City striker lunged into a tackle on Andy Watkins and Whistler Lloyd Wood sent him for an early shower.
Despite the sending off, the Clarets remained in control and successfully held on to secure the three points.
1. Ross Fitzsimons
2. Josh Hill
3. Luke Daley
4. Max Cornhill
5. Chris Bush
6. Michael Spillane
7. Robbie Willmott
8. Anthony Church
9. Louie Theophanous
10. Chris Dickson
11. Shaun Jeffers
12. Elliott Buchanan (84’, off for Chris Dickson)
14. Kane Haysman (66’, off for Shaun Jeffers)
15. Ashley Miller
16. Mark Haines (84’, off for Josh Hill)
18. Daniel Blanchett
1. Max O’Leary
2. Jack Batten
3. Mile Welch-Hayes
4. Chas Hemmings
5. Axel Andresson ©
6. Frankie Artus
7. Andy Watkins
8. Billy Murphy
9. Nick McCootie
10. Marvin Morgan
11. Naby Diallo
12. Josh Hutchinson
14. Shaquille Hunter (75', on for Billy Murphy)
15. Lee Marshall
16. Jim Rollo
Chelmsford City: 23’ Robbie Willmott.
Bath City: 49’ Axel Andresson.
Chelmsford City: 85’ Michael Spillane.
Bath City: None.
Chelmsford City: Michael Spillane (42’), Axel Andresson (59’ OG), Louie Theophanous (76’).
Bath City: Marvin McCootie (13’).
Half-Time Score: Chelmsford City 1-1 Bath City
Full-Time Score: Chelmsford City 3-1 Bath City
Man of the Match: Robbie Willmott
Referee: Lloyd Wood, assisted by Sean Kilbourn and Darren Knox.