Play-off hopefuls Forest Green were sunk by a stoppage-time winner from Dan Creaney to lose 1-0 at Tamworth.
Rovers dominated the first half with D’Mani Mellor putting an early header wide before Tamworth keeper Jas Singh tipped Jayden Clarke’s shot over the top.
The visitors went even closer after the break when Chibby Nwoko clipped the outside of a post at a corner.
Oli Lynch drilled a shot wide midway through the second half for the hosts, before Tamworth snatched the points when Stefan Mols teed up Creaney at the death.
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