A far cry from last week's topsy-turvy battling victory over Tottenham Hotspur, Liverpool this time around were beaten in every department by their opponents.
The Reds saw their three-game run of league victories come to an end against the relegation-threatened south coast side, and they will rightly regard this match as an opportunity lost to continue their charge toward the top five.
It simply didn't happen for Liverpool on Saturday, and here's five reasons why.
With Jamie Carragher unavailable for the match, Martin Skrtel returned to the starting lineup in the centre of Liverpool's defence.
Without bothering to guild the lily, he was quite simply abysmal.
Skrtel didn't track runners inside the area and was slow in reacting to all types of situations on the ground. He failed miserably to cope with Adam Lallana whenever he ran at the defence with the ball at his feet, constantly gave away ridiculous fouls by grappling opponents during aerial duels—including conceding the free kick for the second goal—and was just generally very, very poor.
It continues to be highly evident that the Reds need big reinforcements in this area in summer.
Skrtel had a hand, or rather, a lack of a foot, in all three Southampton goals.
Daniel Sturridge and Philippe Coutinho both had goals ruled out against Southampton for offside, and both decisions appeared correct.
However, a number of other calls went against the Reds to deny them very good attacking chances.
One offside call in particular against Sturridge was a poor decision from the assistant, who should have noted that the striker was at worst level. Sturridge would otherwise have been in for a one-on-one chance from an angle against Artur Boruc in goal.
There was also a bizarre call for a foul by Luis Suarez on Jos Hooiveld, who clearly seemed to simply slip. Suarez would have been through for another chance in the area and looking for his 30th goal of the season, would he have been backed to score.
It didn't happen for the Reds too often, and the officials denied them too often when they did manage to get through.
Quite how Jay Rodriguez was able to sprint through 40 yards of Liverpool territory and tap home Southampton's third goal from close range without a single challenge being made on him should open up the footballing equivalent of a criminal inquiry within the walls of Melwood next week.
The fact that it is far from the first time this season that such a catastrophic lapse in midfield and defence has occurred suggests that such an investigation will not be forthcoming.
Or at least, that the conclusions so far have proved inconclusive as to what the immediate solution is.
Liverpool are badly lacking a powerful presence in the centre of the pitch. Whether Lucas Leiva or Joe Allen plays as the deepest midfielder, there is not enough being done by them (or their teammates, it's not just the defensive midfielder's responsibility) to muscle teams out of possession in dangerous areas or track runners from deep.
This is one of the most serious and pressing issues the Reds must address in summer.
There is no denying that against Saints, Liverpool were far slower, and much sloppier, in possession than they usually would have expected to be. The accuracy and consistency in passing—very much an important part of Liverpool's game—was simply not there.
Unfortunately, when things aren't going well on the ball, the only solution is to work hard and hope that things click into place with concentration and repetition; Liverpool ultimately failed in this respect too.
Simply put, they were outworked, outthought and outfought by a hungrier Southampton side.
Ultimately, when it quickly became apparent that the team selection on the day was not working, Liverpool needed to get some indication from the sidelines that there was a plan in motion to fix things.
A switch to send Coutinho central and Suarez left worked in part; Liverpool retained possession a little better centrally, and Suarez found more space down the channels to be involved in buildup play. Coutinho even scored on the stroke of half time as he was able to be in a more advanced central role.
But the half-time switch of Lucas for Allen, though necessary, did nothing to change the flow of the match.
Southampton were already going to back off more, at least in part to protect their lead, but Liverpool were able to offer nothing new or extra to give themselves more of an effect in the middle and final thirds.
With Jordan Henderson, Suso and would-be-debutant Jordan Ibe on the bench, there were options for Brendan Rodgers to change things around, but the second and final substitute didn't enter the pitch until the final eight minutes of the game, with Liverpool by then 3-1 down.
It wasn't enough from Liverpool, from the players or the management.
Lessons have to be learnt by all parties from this game, and quickly.