Che Adams struck twice as Southampton beat Preston 3-0 to narrow the gap on the Championship's top three.
Stuart Armstrong's classy strike added to Adams' double to all-but end the contest by half-time and virtually end Preston's dwindling hopes of reaching the play-offs.
The win puts the Saints four points behind second-placed Leicester before the two sides meet at the King Power Stadium next Tuesday.
With the top three all faltering and Southampton having won five and drawn two of their last eight - and heading to third-placed Leeds on the final day - the race for automatic promotion from the Championship is now a four-way fight.