Kenny Clark scored the only goal as National League high-fliers FC Halifax lost 1-0 to Southend at Roots Hall.
Clark converted from close range in the 12th minute having been teed up by Jack Bridge.
The hosts went close to scoring again with 20 minutes remaining when Sam Dalby sent a header against the crossbar, with subsequent penalty appeals as he went down while trying to follow up proving in vain.
It was a first loss in six matches for Pete Wild’s third-placed Halifax, who are now only two points ahead of fourth-placed Solihull. Kevin Maher’s Southend remain 13th.
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