Swindon were left staring at relegation to League Two after fellow strugglers Notts County struck twice late on to inflict a 2-1 defeat.
Town, now with only one victory from their last 21 games, could be relegated on Monday but County - under new boss Martin Allen - have registered back-to-back league wins for the first time this season to pull four points clear of danger.
Swindon opened the scoring in the 18th minute following a spell of sustained pressure.
Calvin Andrew rounded Stuart Nelson but saw his goalbound effort cleared off the line by former Swindon loanee Stephen Darby. And from the ensuing corner John-Paul McGovern lifted Alan Sheehan's cross back across goal to find Matt Ritchie, who hammered home from point-blank range.
County, who had previously offered little, left it late but pulled level 12 minutes from time when substitute Alan Judge saw his cross from the left bounce past a possibly unsighted David Lucas.
Worse followed for Swindon fans when poor defensive play let in fellow substitute Lee Hughes who had the simple task of going through and rounding Lucas to score the winner with five minutes remaining.