Swindon looked poor all of the game, and Peterborough weren't much better, but they took their only chance of the game to score.
Peterborough opened the scoring after 34 minutes after a cross from a corner which Evans failed to clear the ball away in time, so Steve Jenkins scored from 5 yards out.
Swindon started the second half looking better, and Sam Parkin came close to scoring when his shot hit the bar.
Henderson also came close to getting another goal on the hour mark, but the Posh 'keeper saved it and pushed it away for a corner.
Andy King then put all 3 strikers up front when he bought on Rory Fallon to replace Mark Yeates, but about from a good run Fallon didn't look like scoring.
Overall a poor game, which unlike Swindon's last home game against Hartlepool Swindon never really looked like the would score. Apart from their goal Peterborough didn't create too much pressure. It was Swindon's worst game of the season so far. Fans in the Town End started to sing "What a load of rubbish towards the end." Swindon's next game is away to bottom of the table Blackpool, who have yet to win a game so far this season.