After a slow start for both teams, Town almost broke the deadlock on 18 minutes when Bevis Mugabi crashed a header off the post from a corner.
Responding at the other end, Abobaker Eisa forced Nathan Baxter into a good save as the opening 45 minutes became a relatively well-matched affair.
Bursting to life after the break, Jake Gray marked his return to the side with a timely first goal of the season that sparked chaos.
In the scenes that followed the opener, U’s goalkeeper Dillon Barnes was shown a straight red card for an off the ball incident to leave the visitors with a man disadvantage.
Riding their luck to not fall further behind the play-off hopefuls battled back to equalise through Tom Eastman as to setup a tense finale.
Town threw caution to the wind in search of a late winner but ultimately had to settle for a point on the board in their bid for EFL survival.
In action for the second time in four days, Neale Marmon made three changes to his starting eleven, two of which were forced.
Shown a red card at Crewe on Good Friday, Adel Gafaiti will play no further part this season through suspension and was replaced by Rhys Browne who returned after a six-week hamstring injury at right-back.
In front of him, Gray was recalled for a first appearance in a month for Alex Fisher as Alex Dobre moved forward to partner Courtney Duffus, who took the spot of the injured Ryan Seager (knee).
In the only other team news, Mugabi retained his spot in defence to make his 100th appearance for the club since joining in 2016.
Bathed in scorching sunshine in Somerset the opening 10 minutes passed with little action of note, as both sides settled into proceedings.
In a routine save for Nathan Baxter, Tom Eastman headed straight into the keeper’s arms from a Eisa corner whilst the home faithful created a vocal atmosphere in full support of the hosts.
Cheered on by their 12th man the Glovers came within a post’s width of taking the lead just before the 20-minute mark.
Tristan Abrahams’ deep corner was met by the giant leap of Mugabi, but the defender’s header came off the outside of the post to deny him a perfect way to mark his milestone appearance in green and white.
Having come close at one end, Town almost fell a goal behind at the other after good hold-up play from Frank Nouble.
Teeing the ball up for Eisa to strike Baxter had to be alert to parry away the shot that came through a host of bodies 18-yards out.
Beginning to open up after a tentative start both sides began to work the ball into shooting areas, as Gray and Eisa both had efforts comfortably saved before an injury blow for the hosts.
Browne’s return from a hamstring injury lasted 35 minutes as he went down unable to continue, allowing Academy product Daniel Ojo to take his place.
The first of a series of disruptions the remainder of the first-half became a stop-start affair as chances remained at a premium in a match that saw both teams desperate for points at opposite ends of the table.
After the restart, and playing with more intensity, the roof was lifted off of Huish Park on 53 minutes when the Glovers opened the scoring.
Only clearing the ball to Gray 20-yards out, the midfielder wasted no time in firing a left-footed strike that deceived Barnes and nestled in the bottom corner.
In the pandemonium that ensued Barnes kicked out at Abrahams as the celebrations continued, an action spotted by referee Peter Wright who swiftly awarded a red card to the U’s stopper.
Down to 10, Sam Saunders was sacrificed to allow sub keeper Ethan Ross to enter the fray but the stunned visitors almost responded immediately.
Frankie Kent rose highest to meet a Eisa corner, but the defender’s towering header cannoned back off the bar as Baxter could only watch on.
Having survived that scare the green and whites went on the offensive and looked like adding to their lead.
Dobre lashed a strike weide of the target after intricate link-up play on the edge of the box before Tom James had his dipping 30-yard free-kicked tipped over by an alert Ross.
However, having come closest to scoring through set-pieces, John McGreal’s side were to silence BA22 as the game ticked into the final quarter-of-an-hour.
Brennan Dickenson’s corner could only be flicked into the path of Eastman who kept his composure to fire the ball back in the direction where it came from and tee up a tense final 15 minutes.
Roared on by the home faithful, Marmon introduced more firepower in the form of Yoann Arquin and Fisher to throw caution to the wind in a last bid to try and claim a vital three points.
A succession of corners were earned deep into the six minutes of additional time but there was to be no more drama as both sides had to settle for a share of the spoils.
Yeovil Town: Baxter; Browne (Ojo 35′), Sowunmi, Mugabi, James; Gray, D’Almeida, Pattison (Arquin 76′), Abrahams; Dobre, Duffus (Fisher 86′).
Subs not used: Nelson, Worthington, Rogers, Zoko.
Colchester United: Barnes; Jackson, Eastman, Kent; Eisa (Mandron 68′), Lapslie, Saunders (Ross 55′), Senior (Norris 80′), Dickenson; Nouble.
Bookings: Barnes (sent off) 55′, Lapslie 70′
Subs not used: Kensdale, Stevenson, Wright, Chilvers.