Danny Ings took his tally to 21 goals for the season with one in each half at Watford, as Southampton chalked up an eighth Premier League away win of the season to reach 40 points in impressive style.
Ings was deadly in finding the target from his only real chances of the game – the first a well-placed low shot from the edge of the box; the second a driven effort across goal as he profited from a loose throw from Watford goalkeeper Ben Foster.
An own goal from the unfortunate Jan Bednarek gave hope to the home team, but that was instantly extinguished by a trademark James Ward-Prowse free-kick.
Ralph Hasenhüttl promised changes to his team and duly switched half of his outfield players, with Jack Stephens suspended, Pierre-Emile Højbjerg injured and Yan Valery, Stuart Armstrong and Michael Obafemi dropping to the bench.
In came Jannik Vestergaard, Kyle Walker-Peters, Oriol Romeu, Will Smallbone and Shane Long, who broke the Premier League record for its fastest ever goal on his last visit to Vicarage Road.
No sooner had both sets of players risen from their knee in support of the Black Lives Matter campaign than the heavens opened, as kick-off was greeted by a torrential downpour in stark contrast to the scorching heat of St Mary’s only three days prior.
The hosts posed an early threat when the lightning-quick Ismaïla Sarr raced in behind and cut the ball back from the byeline, but none of his teammates were in position to pounce in the box.
Ings was involved for the first time shortly before he opened the scoring, as he combined with strike partner Long, who connected cleanly on his left foot but shot too close to Ben Foster.
Moments later Ings moved into joint second place in the Premier League Golden Boot race, dropping a shoulder to elude Craig Cathcart and planting a low, precise 20-yard strike into the bottom corner past the unsighted Foster.
Proving his contribution runs far deeper than his goals, Saints’ talisman made the most of an overhit pass to win a free-kick wide on the left, from which he threw himself at Ward-Prowse’s wicked delivery and was inches away from getting a touch that would have left Foster stranded.
At the other end, Sarr’s pace remained Watford’s best outlet, and Ryan Bertrand endured a heart-in-mouth moment when he pulled the winger’s shirt in the box, prompting Sarr to stop and referee Michael Oliver to consult VAR, but the verdict was that both players were holding each other, as Saints survived a rare scare just before half time.
Hornets boss Nigel Pearson would have demanded a reaction and his team did not take long to up the ante, as Sarr was again involved only to be thwarted by an outstanding block from Bertrand inside a crowded penalty area, before Troy Deeney fired over from distance.
The game was opening up, as the hosts committed more men forward whilst Saints sought a second goal on the counter-attack, prompting Stuart Armstrong to replace Smallbone, who had assisted Ings’s first goal.
When the drinks break was called midway through the second period, Foster may have been guilty of losing concentration, unlike the razor-sharp Ings, who read the keeper’s intentions to intercept his throw out, surged into the box and scored again via a slight deflection off Craig Dawson.
Make that 21 in all competitions, 18 in the Premier League and within one of Golden Boot race leader Jamie Vardy.
The marksman nearly turned provider for Nathan Redmond shortly after, only for the winger to shoot wide, before Ché Adams arrived from the bench to replace Long as Ings’s partner in crime.
Just as Saints looked to be out of sight, substitute José Holebas delivered a teasing cross from the left that forced Bednarek to deal with it in front of the poaching Danny Welbeck, and the Pole could only succeed in sliding the ball beyond Alex McCarthy at the near post.
That may have sparked an anxious finale, but Ward-Prowse punctured Watford’s renewed optimism with a free-kick from his favourite spot, leaving Foster a mere spectator as Saints celebrated another victory on the road.
All that was missing was a first goal for Adams, who must have thought his moment had arrived when he showed a clean pair of heels to Dawson and went eye to eye with Foster, only for the keeper to get just enough on his attempted finish to keep the striker at bay.
There was still time for Redmond to come even closer, crashing a shot against the base of the post as Saints underlined their superiority.
Only Liverpool and Man City have won more Premier League away games this season than Hasenhüttl’s team, who climb to 13th and are now just two points off a place in the top half.
Shots on target00
Line ups not available