An injury to Southampton’s Gavin Bazunu during the warm-up thrust Alex McCarthy into the starting lineup for his first Championship start of the season.
The Saints’ backup goalkeeper had to be on his toes early on to grasp Mads Frøkjær-Jensen’s early poked attempt from close range.
It proved to be Preston’s only sniff at goal in the opening stages, as the Saints took full control of the game and put North End to the sword with three goals in 13 minutes, starting with Ché Adams tucking in his third goal in as many games from Adam Armstrong’s low cross.
Adams wasted no time extending Southampton’s lead when the Scottish international dummied Ryan Manning’s pass to David Brooks, who fed the ball back to Adams to curl past Freddie Woodman.
Another Scot was also keen to get in on the action and Stuart Armstrong set Russell Martin’s side on their way to a third successive win, with a dipping strike from 20 yards that had Woodman rooted to the spot.
Preston were in danger of conceding four goals for a fifth time this season, but the woodwork kept the damage to a minimum after Stuart Armstrong’s strike cannoned off the post and flew across the goalmouth.
Preston faced an uphill battle, especially as the Lilywhites failed to score in their last two away matches, and the visitors struggled to find a moment of quality to spark a comeback.
Southampton were in command and Adams continued to provide the attacking focal point with a darting run and shot that Woodman kept out.
Ultimately, Woodman kept the Southampton scoring to a minimum as the Preston goalkeeper’s fingertip save denied David Brooks' stinging shot.
Southampton have firmly established themselves as late Championship promotion candidates following just one defeat in eight.
However, stern tests are yet to come as Martin’s side face two season-defining fixtures at Leicester and Leeds in their final four matches.
After Frøkjær-Jensen’s early stab at goal, Preston rarely got out of their half and a return of four points from five matches has effectively ended a late play-off charge for Ryan Lowe’s side.
Flashscore Man of the Match: Ché Adams (Southampton)