Junior Firpo scored his first Premier League goal as new manager Javi Gracia began his reign at Elland Road with a priceless three points to take his side out of the relegation zone.
In a nervy relegation six-pointer, Firpo broke forward from full-back to squeeze home the winner after 77 minutes and earn his side their first win since Bonfire Night.
Saints stay bottom as a result and few will have sympathy for the spoiling tactics they employed until falling behind.
Gracia made just one change on his debut with Brenden Aaronson replacing Crysencio Summerville. But there was a tactical tweak with the American pushed up front to join Patrick Bamford in a two-pronged attack.