Southampton suffered a first defeat since the middle of January as Aston Villa capitalised on a sub-par performance from the visitors in the Premier League.
The afternoon got off to a difficult start, as with just nine minutes on the clock Ollie Watkins gave the hosts the lead from the game’s first meaningful attack.
Enduring a barrage of pressure at the end of the first half, Saints found themselves two down at the break as Douglas Luiz put the hosts firmly in the driving seat.
With the half-time break doing little to limit Villa’s momentum, the game was put beyond the reach of the visitors courtesy of two in two minutes from Philippe Coutinho and Danny Ings, who was to come out on top on his first outing against his former club.
Having named an unchanged side in the last two Premier League outings, Ralph Hasenhüttl was forced into two changes for the trip to the Midlands.
Mohammed Salisu’s hamstring injury ruled him out of action while Kyle Walker-Peters was only fit enough for the bench having been withdrawn in midweek, allowing Jack Stephens and Romain Perraud - fresh from his spectacular first goal for the club on Wednesday - to come into the back four.
Up front there was a milestone for Ché Adams, who made it a century of Southampton appearances since joining in 2019.
Many of those 100 appearances would have come alongside one-time teammate Ings, who lined-up on Saturday afternoon in claret and blue.
Missing the reverse fixture due to injury, the 29-year-old was quick to make an impact by providing an assist just nine minutes in.
Picking out the run of Watkins, the striker cleverly turned on the ball with his first touch to lose the attention of Stephens, before curing a strike into the back of the net from just inside the box.
Despite conceding a first Premier League goal in three games, Saints were far from deterred and came close to an equaliser on 17 minutes.
With the trademark high press resulting in Armando Broja winning possession deep in Villa territory, his square ball to Stuart Armstrong culminated with the Scotsman’s curling effort drifting agonisingly wide of Emiliano Martínez’s goal, with the Argentine rooted.
Teasing at an end-to-end affair the contest instead drifted up until the half-hour mark, when the game burst back into life as Forster made a superb save.
As another Watkins run in behind was this time spotted by Coutinho, the Saints stopper was quick off of his line to narrow the angle and get a vital trailing right leg to the striker’s low shot at goal.
Before many inside Villa Park had digested the hosts’ chance to double their led, it was almost made all square at the other end.
Tino Livramento’s hung up cross to the back post had both Adams and Moi Elyounoussi interested, but it was the Scotland international who rose highest before seeing his header loop onto the roof of the net.
However, as the half-time whistle drew closer it was the Villains who moved into the ascendancy once more.
The mercurial Coutinho was presented with two pristine chances to make it two, first blazing a loose ball from a Matty Cash cross just wide of the target, before missing a more guilt-edged chance as Watkins’s pull back could only be placed where Forster could get an outstretched leg to it from eight yards out.
With the yellows in a state of flux, the Lions smelt blood and pounced to produce a second on 44 minutes.
Calum Chambers’s ball over the top perfectly matched the run of Coutinho, whose first-time ball back across goal couldn’t be missed by Luiz.
As the home faithful celebrated it could, and perhaps should, have been 3-0 before the break.
A routine Martínez clearance suddenly screamed danger when Watkins won the flick-on to set the all-action Coutinho clean through on goal, but the Brazilian skewed wide to offer Hasenhüttl’s side a needed lifeline heading into the second period.
In an attempt to turn the tide, Yan Valery was introduced at the halfway stage as Saints moved to a back three, but the waves of Villa attacks continued to batter Southampton’s defence which was breached once more on 52 minutes.
Guilty of wayward finishing in the first half, Coutinho was clinical this time around. Collecting a flicked pass from Ings in the box, the Brazilian feigned a shot to engineer a yard of space, before drilling past Forster in front of the Holte End.
Haunting his former side with two assists, Ings was now determined to get on the scoresheet, and was only denied by a superb Forster stop moments after Coutinho’s third.
However, the wait was only momentary as the striker produced a finish seen countless times in red and white as he swept home Cash’s low cross from 12 yards for Villa’s second in two minutes.
As the floodgates threatened to open, Saints regrouped and attempted to at least reduce the four-goal deficit with the result seemingly unsalvageable.
Adams, on an unenjoyable 100th appearance, forced Martínez into a smart stop after racing into the box at an acute angle, before a menacing James Ward-Prowse delivery from a corner needed Ashley Young to head over his own bar after Stephens won the initial header.
A difficult afternoon wasn’t to have any form of consolation, though, as the hosts successfully shut up shop to end Southampton’s run of scoring in 10 consecutive Premier League games and inflict a heavy first defeat in eight matches in all competitions.