In-form Lincoln City remain in the promotion race after securing a well-deserved victory at Southend.
Ben Futcher's tenth minute header consigned the Shrimpers to their third successive defeat as Rob Newman's side remain locked in mid-table.
Ben Sedgemore fired Alan Pearce's flick over the bar in the opening stages before Keith Alexander's side took the lead when the lanky Futcher got up well to head Sedgemore's corner into the top corner of the net.
Southend did their best to hit back with Dominic Foley just failing to get on the end of Kevin Maher's throughball before Daniel Marney fired a long-range effort over the bar.
However, the Red Imps continued to look dangerous with Sedgemore and Simon Weaver going close to extending their lead.
Richard Butcher also went close before the break while Peter Gain's effort was well saved by Darryl Flahavan.
After the interval Leon Cort headed straight at Alan Marriott while Tes Bramble was also denied by the Lincoln keeper.
Southend piled on the pressure in the closing stages in the vain hope of snatching an equaliser but Neil Jenkins blasted a late effort wide as the visitors hung on to win.