The decision comes just two days before the Gas host the Cobblers in Sky Bet League One on Saturday.
That was achieved with a remarkable and controversial 7-0 final day win over already-relegated Scunthorpe United, meaning Rovers pipped Jon Brady’s Cobblers to a third place finish on goals scored.
“Everyone at the club would like to thank Joey for all his efforts and wish him well in the future.
“In the interim, Andy Mangan will lead the team supported by Glenn Whelan, Danny Ventre and Anssi Jaakkola who will remain in post.”
Barton leaves the club with the Gas sitting in 16th place in the league one table, three places and two points better off than the Cobblers.
They have won three, lost three and drawon one of their past seven league matches, Barton’s final game in charge proving to be last Tuesday’s 1-1 home draw with Stevenage.
They finished 17th in league one last season, eight points above the drop zone.
