Swansea City were left staring into the Premier League abyss after a 1-0 defeat at home to relegation rivals Southampton.
After 72 minutes of frenetic action, substitute Manolo Gabbiadini provided the decisive moment when he reacted quickest to Charlie Austin's parried shot in a crowded goalmouth.
It means Saints are all but guaranteed Premier League survival, while the result condemned West Brom to the drop.
Southampton now have 36 points - three more than Swansea, who entertain relegated Stoke on Sunday.
The Saints' goal difference is also nine better than Swansea's, so they will be safe barring a significant turnaround.
Huddersfield also remain in the mix given the poor state of their goal difference, although one point from remaining games against Chelsea and Arsenal will ensure they finish above Swansea.
Swansea Manager Carlos Carvalhal says the Swans will "play their part" to avoid relegation with one game left, but he knows their fate is not entirely in their own hands.
Swansea's best chance of survival rests on overcoming Stoke and seeing Huddersfield lose their final two games, at Chelsea on Wednesday and at home to Arsenal on Sunday.