By Rob Bishop
Villa endured a second half nightmare at St Mary's as newly-promoted Southampton stormed back for their first Barclays Premier League win of the season.
Leading at the interval through an opportunist Darren Bent goal, Paul Lambert's men looked to be on course for three points, particularly when they opened the second half in such positive fashion.
But it all started to go wrong after Rickie Lambert produced a 58th-minute equaliser.
Full-back Nathaniel Clyne put the Saints ahead five minutes later, Jason Puncheon hit a third, and Lambert completed the scoring with a stoppage-time penalty.
Home skipper Adam Lallana provided Villa with a few problems during a generally tepid opening 20 minutes.
The winger, recently called into the England squad, swept menacingly down the left before being halted by the back-tracking Karim El Ahmadi, and then burst through the middle to set up Rickie Lambert for a shot which was well over.
Former Villa midfielder Steven Davis also lacked direction with a drive which went harmlessly wide, but Gaston Ramirez was much closer with a low shot which wasn't far off target.
The visitors were struggling to find any rhythm at that stage, although it took a well-timed tackle by Jose Fonte just inside the penalty area to prevent striker Bent from capitalising on Stephen Ireland's pass.
After Brad Guzan had saved comfortably from Lallana's overhead kick in a crowded goalmouth, Barry Bannan hit Villa's first shot in the 32nd minute.
Unfortunately the Scot's left-foot volley from the edge of the area, following Brett Holman's fine pass and Ireland's deep cross from the right, was wide by some distance.
Having barely threatened, though, the visitors grabbed the lead on 35 minutes.
Bannan's deep centre from the left was headed back across goal by Bent, and although the ball was headed away, it only went as far as Ireland on the edge of the area.
The midfielder miscued his shot but Bent reacted smartly to nudge the ball just inside the near post from six yards as home defenders hesitated.
The Saints' response was immediate but inaccurate, Jason Puncheon firing wide as he fell, but Villa might easily have doubled their lead during an early second-half onslaught.
After a quiet opening period, Christian Benteke suddenly came to life to underline just why Lambert was so keen to sign him.
The Belgium international initially provided a superb crossfield pass to set up Bent for a left-footer which was pushed away for a corner by keeper Paulo Gazzaniga.
From Bannan's flag kick, Bentike nodded forward for Ciaran Clark to get in a header which deflected over off a defender's head.
And when Bannan delivered a second corner from the left, Benteke's powerful header flew a foot wide of the far post.
Villa's best attacking spell so far, unfortunately, was merely the prelude to a Southampton equaliser on 58 minutes.
Lallana's clever turn on the right enabled him to get in a dangerous cross which evaded Ron Vlaar, and Lambert quickly controlled before drilling a fierce 15-yard shot which Guzan parried but could only help into the net.
Five minutes later the home side were ahead, Clyne moving on to a deft flick from Ramirez to drive low past a helpless Guzan.
And on 72 minutes the situation deteriorated further, Puncheon moving on to Lambert's short pass and turning inside Matt Lowton before sending a rising, angled shot which hit Ciaran Clark and flew into the top corner.
There was nearly another when substitute Mayuka fired narrowly wide from the edge of the area, although Bent almost reduced the deficit with a 22-yard free-kick which curled over the bar.
Just when it seemed things couldn't get any worse, Lambert drilled home his second from the spot after Guzan had brought down Mayuka.
Southampton: Gazzaniga; Clyne, Fonte, Yoshida, Fox (Richardson, HT); Schneiderlin, S Davis (Ward-Prose, 79), Puncheon (Mayuka, 74) Lallana; Lallana; Ramirez, Lambert. Unused subs:K Davis, Rodriguez, Do Prado, Seaborne.
Villa: Guzan; Lowton, Vlaar, Clark, Lichaj (Bennett, 68); Holman, Ireland (Westwood, HT), El Ahmadi, Bannan (Agbonlahor, 68); Bent, Benteke. Unused subs:Given, N'Zogbia, Bowery, Weimann.