The Saints stay on top of the Championship but the marching in will have to wait for another day, Kenny Miller having halted their progress with his first goals since the winner against West Ham United in Cardiff City's first match of the season.
The second and third have been a long time coming for the Scotland striker, who cost Cardiff £750,000 from the Turkish club Bursaspor in July, but the fans were prepared to forgive him for that on Wednesday night, when they acclaimed him volubly as "The King".
The Welsh team are unbeaten in eight games, back in the play-off places in sixth and only three points off the top. That said, their shortcomings in front of goal of late have condemned them to too many draws, and Malky Mackay had been searching for a proven striker to sign on loan. As of Wednesday he had enquired about six and got nowhere.
Miller came to the rescue here with two well-executed finishes. The first, after 55 minutes, was the product of a long clearance from the goalkeeper, David Marshall, which carried over Southampton's culpably hesitant centre-halves. The Scot made short work of beating the advancing Kelvin Davis to the ball and heading it into the unguarded net. The second, eight minutes later, saw Miller fasten on to Aron Gunnarsson's pass to score with a precise shot.
Running the channels with energy and pace, the former Rangers striker for the first time looked the part as the replacement for Craig Bellamy. "I'm looking to kick on now and start scoring more regularly," Miller said. "To be fair, the chances have been few and far between. If you're getting three and four [chances] every game you should be scoring your share, but if it's only one or two it's hard."
After a barren first half, in which neither keeper was called upon to make a save, the game caught fire in the second, when Southampton had their moments. On this occasion, though, the prolific Ricky Lambert and his capable assistants, David Connolly and Adam Lallana, with 14 goals between them, were unable to maintain their productivity, Lambert wasting his team's best chances with two poor headers. Steve de Ridder, on as substitute, pulled one back in injury time, but it came too late to deny Cardiff a morale-enhancing victory.