Ralph Hasenhuttl has repeatedly said that you need a perfect performance to beat a top six team.

He may want to change that to a perfect half.

For Saints certainly produced no more than one complete half of excellent football at St Mary’s, but it was good enough to secure a thrilling victory that does so much to help their survival prospects.

At half time things looked bleak.

Saints had been battered by Tottenham and the game really should have been out of sight.

Something had to change at the break, and Ralph Hasenhuttl wasn’t afraid to get stuck in.

His double substitution, bringing on Josh Sims and Shane Long, added pace, urgency, pressing and threat in behind and turned the game on its head.

The significance of this win, not only a first after falling behind this season and such a rare victory over Tottenham in recent times, is huge.

You can imagine the joy at Cardiff as they realised they were going to see out a home win against West Ham.

They must surely have expected that would be enough to lift them out of the bottom three for the next three weeks. Imagine the deflation when they came off to see that Saints had beaten Tottenham, and in a way that creates such positivity and momentum at St Mary’s.

Staying out of the bottom three heading into this unwelcome break in action was so important for Saints.

It just keeps the edge of that pressure off of them – and it would have been intense had they not won on a day that Cardiff, Brighton and Newcastle all had - when they come back for what looks a huge game against Brighton.

What they needed to avoid was the feeling that they had to win that match because Liverpool are next up at St Mary’s. They needed, above all else, to avoid dropping into the danger zone with then six games to go when results become more unpredictable.

There is every chance they can do that now.

Add to that the confidence that naturally comes with a victory like this, and on the back of the Fulham and Manchester United games. The only shame for Saints is that they need to step back before they can go again.

At least, though, it can be three enjoyable weeks of hope and optimism rather than wracked with fear and worry.