Unfortunate Prosser own goal results in narrow defeat for the Blues.
An unfortunate own goal by Luke Prosser resulted in the end of Blues' three-game winning run with a narrow 1-0 defeat to league leaders Burton Albion.
Following an even first 45 minutes, the Brewers took the lead after the break as Prosser deflected a Tom Naylor strike into his own net.
Manager Phil Brown named an unchanged starting XI again for the game against Burton Albion, following a run of three consecutive wins.
This means that two-goal hero Joe Pigott keeps his place in the side alongside David Mooney, with Michael Timlin keeping the armband in the absence of regular skipper John White.
It was a bright start from the hosts and after only eight minutes, schemer Nasser El Khayati – who scored the winner against Blues at the Pirelli last season – saw his strike deflected just over Dan Bentley's upright.
Soon after and the Brewers had another chance through captain John Mousinho.
It all came from a pinpoint Mark Duffy cross from the right but Mousinho could only head wide when well placed.
The best chance Blues had was a header from Joe Pigott, which was scrambled clear by Brewers goalkeeper Jon McLaughlin.
In truth, it was a half of few chances for either side as the teams went in at the break all square.
The hosts came flying out of the traps for the second half and went close through Duffy's effort which went into the side-netting via a deflection.
And moments later Jimmy Floyd Hasselbaink's side took the lead through the unfortunate Prosser.
Tom Naylor's left-footed effort was going well wide of the target, but the attempt cannoned off Prosser and flew past Bentley, who stood no chance of keeping the ball out.
Burton's tails were up and they pressed for a quick-fire second to add to their tally.
Duffy was a menace all game and he curled just inches over Bentley's bar and onto the roof of the net on 55 minutes.
At the other end, Prosser almost made amends for his earlier misfortune but could only head well wide of the target following Pigott's nod back across goal.
With 17 minutes remaining, Pigott had a great chance to score his third goal in a week.
A great boot upfield from Bentley bounced through to the striker, who tried to loop the ball over McLaughlin, but the attempt was tame and the opportunity was gone.
With eight minutes remaining, and having already utilised Myles Weston and Anthony Wordsworth, Brown threw on Jack Payne in an attempt to find an equaliser.
And moments later Payne's pass fed Weston, whose cross was good, but Mooney would only head straight at McLaughlin.
Try as they might, Blues couldn't find a way through a resolute Burton backline, as Hasselbaink's men kept their spot at the top of the league.
For Southend, they turn to JPT action on Tuesday evening against Crawley Town.
Blues: Bentley; O'Neill, Bolger, Prosser, Coker; Worrall (Weston, 56), Deegan (Payne, 82), Leonard, Timlin (c) (Wordsworth, 65); Mooney, Pigott
Unused substitutes: T. Smith, Atkinson, Rea, Williams.