Andrew headed in a first-half corner and Alan Marriott made a string of saves for Mansfield before Chesterfield midfielder Gary Roberts was shown a straight red card in stoppage time.
High-flying Oxford racked up their fourth away win of the season with a 3-1 triumph at Hartlepool United.
Rochdale resisted Wycombe's fightback to claim their fourth successive victory in a 3-2 win at Spotland.
The visitors were caught cold as Rochdale raced into a 3-0 lead inside the opening 15 minutes before Matt McClure’s stinging low drive and Jo Kuffour’s lofted effort set up a tense finale.
Makeshift striker Scot Bennett scored twice in three minutes as Exeter came from behind to defeat in-form Fleetwood 2-1.
The Cod Army took the lead through Matty Blair with 19 minutes to go yet Bennett's three-minute double salvo shortly afterwards turned the game on its head.
Substitute Jamie Cureton was Cheltenham's last-gasp hero, scoring the only goal in the dying seconds to secure a first home win of the season for Mark Yates' side against Wimbledon.
The former Exeter striker, back on the pitch after a spell sidelined with injury, latched onto a huge clearance from Scott Brown, celebrating his 250th appearance for the club, and beat Ross Worner with an expect finish to earn the Robins their first home league win of the season.
Plymouth Argyle failed to make the most of gilt-edged opportunities as they drew 0-0 at home with basement side Accrington Stanley.
The closest Argyle came to breaking the deadlock was in the fifth minute when winger Rommy Boco's angled drive from the right edge of the box clipped off the outside of the far post with outstretched Stanley keeper Marcus Bettinelli beaten.
York registered their first win since the opening day of the season with an emphatic 4-2 victory over Portsmouth whilst there were also wins for Dagenham & Redbridge, who beat Bury 2-1, and Newport, who edged Torquay 2-1.
Burton secured a 2-2 draw with Scunthorpe whilst Northampton and Morecambe couldn’t be separated in a goalless draw.