Blues fell to a narrow 1-0 defeat away at Cheltenham Town with a second-half penalty from Conor Thomas the difference at the Jonny-Rocks Stadium.
The much-changed Southend side, which included emergency loanee goalkeeper James Montgomery, held firm in the first-half against an onslaught of long throws but their defences were breached early after the restart when Shaun Hobson gave away a penalty.
Hobson brought down Callum Wright, with referee Will Finnie immediately pointing to the penalty spot, allowing Thomas to send Montgomery the wrong way and send the Robins top of the League Two table.
The defeat brought to an end an unbeaten away run of three games for Blues who remain outside the relegation zone after defeats too for Barrow and Grimsby tonight, ahead another huge clash for Southend away at Oldham Athletic on Saturday.
Tonight’s trip to Cheltenham was the first of seven matches in a hectic March and with Blues boss Mark Molesley expecting an aerial onslaught from the Robins, the Southend manager made use of his squad by making six changes to the side that had started against Salford.
Tyler Cornder and Greg Halford came in to add some more height to the Blues defences and they were needed to repel Ben Tozer’s long-throws which were one of Cheltenham’s main weapons in a first-half short of clear chances for either side.
Southend had shown some good form on the road of late and they created the game’s first chance when Tom Clifford and Ricky Holmes – making his full debut for Blues – linked down the left, with Holmes seeing his first shot blocked before the rebound was fired wide from a tight angle.
The Robins, who knew that a win could send them top of the table, had a couple of half-chances with Matty Blair and Callum Wright failing to hit the target. Further efforts from Charlie Raglan and Sam Smith were then easily held by emergency loanee James Montgomery.
After the restart though, Cheltenham broke the deadlock as they won a penalty for a foul on Wright by Shaun Hobson. It looked like the Leicester loanee was looking for the contact, but referee Will Finnie pointed to the spot, with Conor Thomas sending Montgomery the wrong way to score.
Mark Molesley reacted to going behind by calling for the cavalry and made a triple change on the hour mark with Reeco Hackett-Fairchild, Nathan Ferguson and Simeon Akinola all being thrown on to try and retrieve a point or even three.
And with less than 10 minutes remaining Southend created their best chance to equalise when Hackett-Fairchild’s cross found Timothee Dieng. The Frenchman though failed to get the desired contact with his header as it went wide when anything on target would have caused problems.
Southend threw everything they could forward to try and force an equaliser but were unable to trouble Josh Griffiths in the Robins goal, as Michael Duff’s side went top of the League while Southend remain two points above the drop zone.
Cheltenham Town XI: Griffiths, Long, Hussey, Tozer (C), Raglan, Thomas, Smith, May (Williams 75’), Blair, Azaz, Wright (Sercombe 76’). Subs Not Used: Flinders, Freestone, Horton, Chamberlain, Vassilev
Blues XI: Montgomery, Hobson, Cordner, Dieng, Clifford, Acquah (Hackett-Fairchild 60’), Nathaniel-George (Goodship 84’), Halford (K Taylor 78’), Demetriou (Akinola 60’), Holmes (Ferguson 61’), White (C). Subs Not Used: Seaden, McCormack
Referee: Will Finnie
Assistants: Kevin Howick & Christopher Kidd
Fourth Official: Carl Brook
Cheltenham Town: Conor Thomas (p)53’
Southend United: None
Cheltenham Town: None
Southend United: None