Chesterfield had to settle for a point at Colchester United, drawing 1-1 after taking a first-half lead.
Louis Reed put the Spireites ahead shortly before the interval but Brandon Hanlan equalised eight minutes from time.
Manager Gary Caldwell made three changes to the starting line-up following Saturday's defeat at Crewe Alexandra.
Diego De Girolamo, on loan from Bristol City, was handed his full debut for the Spireites while Robbie Weir returned after serving a one-match ban and there was also a recall for Bradley Barry. They replaced Chris O'Grady, Andy Kellett and Ian Evatt with the former pair among the substitutes.
Jordan Flores picked out Kristian Dennis in the area early on, but the striker was unable to control the ball and a defender cleared.
Colchester, who beat Crawley Town 3-1 at the weekend, had the first chance of the match when Sammie Szmodics put a rising shot over from around 20 yards out.
There was a scare for the Spireites in the 19th minute when Mikael Mandron headed on to Nicke Kabamba who directed a header on target, forcing Tommy Lee to fling himself to his right to turn the ball wide.
Lee came to his side's rescue again just after the half-hour mark, saving from Szmodics' well-struck 25-yard drive.
Szmodics put another shot on target a couple of minutes later after finding some space in the area and again Lee was equal to it, saving comfortably.
Dennis had sight of goal after receiving the ball from Flores, forcing Sam Walker to make a save.
Moments later, at the other end, Ryan Jackson put a firm shot over.
Chesterfield made the breakthrough when Reed (43) produced a fine finish, firing into the roof of the net after a lay-off from Dennis.
De Girolamo went close to adding a second after being put through, forcing Walker to save.
Zak Jules also hit the side netting as Chesterfield finished the half strongly.
The hosts threatened early in the second half when Lee spilled the ball from a low cross delivered by Cameron James, but Sam Hird was on hand to clear.
There was another let-off for the Spireites when Kabamba shot wide after being through.
A chance fell to Matthew Briggs when Dennis' cross from the right found him unmarked inside the area, but he was unable to direct his first-time effort on target.
As Colchester looked to get back on level terms, Jackson tried his luck from distance but Lee made a comfortable save.
Caldwell made his first substitution midway through the second half, sending on O'Grady in place of De Girolamo.
The home side were awarded a free kick inside the 'D' and substitute Drey Wright took it, putting his effort over the bar.
Goalscorer Reed was replaced by Jack McCourt in the 73rd minute.
Flores and Dennis again linked up well, with the former producing a neat bit of skill before laying the ball off to Dennis whose long-range effort was straight at Walker.
Colchester went desperately close to levelling in the 76th minute when a curling shot from Kane Vincent-Young beat Lee but came back off the bar.
The Spireites had another escape when Tom Eastman's shot was blocked by Weir on the line and Zak Jules cleared the loose ball.
The equaliser came in the 82nd minute when Jackson's long throw was met by a flicked header from Hanlan.
Caldwell made his final change six minutes from time, replacing Dennis with Gozie Ugwu.
The woodwork came to Chesterfield's rescue again when Wright's low cross came back off Lee's right-hand post.
Lee was then called in to action to claim the ball from a Ryan Inniss header while Brandon Comley shot over in stoppage time.
Colchester: Walker, Jackson, Lapslie, Szmodics (Odelusi 89) Comley, Kabamba, Eastman, Mandron (Hanlan 71), Vincent-Young, Inniss, James (Wright 67)
Chesterfield: Lee, Hird, Wiseman, Barry, Jules, Briggs, Weir, Flores, Reed (McCourt 73), De Girolamo (O'Grady 67), Dennis (Ugwu 84)
Unused substitutes: Anyon, Sinnott, Maguire, Kellett.
Attendance: 2,552 (117 Chesterfield fans)