Southend suffered a blow in their chase for the League Two title as they went down at Aldershot.
The Shrimpers, who began the day in top spot, conceded first when Adam Mekki's deflected strike wrong-footed goalkeeper Glenn Morris.
Josh Payne then doubled the Shots' lead with a clinical penalty, after Morris had brought down Mekki in the area.
The visitors almost grabbed a goal late on, but Elliot Benyon's header flew just over the bar.
VIEW FROM THE DRESSING ROOM
Aldershot manager Dean Holdsworth told BBC Surrey:
"There was a massive desire to perform against the team who were top of the league before the game, so full respect to Southend, but full respect to my players for giving everything they've got.
"I thought Adam Mekki was outstanding, Josh Payne was superb in there. The desire and the character of the players, and the team spirit is certainly growing.
"We know its going to be a hell of an ask for the rest of the season, but when you're winning, it breeds confidence. We won't get complacent, we know what we want to achieve. We need to make sure we manage the players, and move on."
Southend United manager Paul Sturrock told BBC Essex:
"There are certain words in football that are used quite regularly about a performance.
"I think gutless is the word I would have to use (this time).
"We could have played another 90 minutes and never looked like scoring.
"We seem to be that kind of team at this minute in time who cannot seem to push ourselves in the right manner to get into the right position for the game."