Swindon midfielder Jonathan Smith came off the bench and inspired his team to victory over Southend.
Mehdi Kerrouche's header hit the visitors' crossbar, before Blair Sturrock's close-range header was saved by Swindon keeper Mattia Lanzano.
Smith notched his first goal of the season with a right foot piledriver, which flew into the bottom corner.
And Kerrouche made the points safe, sweeping home after neat interplay between Simon Ferry and Matt Ritchie.
VIEWS FROM THE DRESSING ROOM
Southend boss Paul Sturrock told BBC Essex:
"I think some home truths are going to have to be said. Two or three of the players' form has deteriorated.
"And the thought process as far as when they are playing the game is concerned, when the other team has the ball, has been very disappointing.
"There's a few bruised egos, there's a few others who have probably played their last game for a long time for this football club."
Swindon Town manager Paolo di Canio told BBC Wiltshire:
"To win two games in a row after a bad run is crucial.
"The lads feel more confidence in the way we play.
"I can only be happy today, we scored at important times."