There was late heartache on the south coast for Sam Allardyce and his Sunderland players.
Jermain Defoe put the Black Cats in front to send the travelling supporters into ecstasy.
But former transfer target Virgil van Dijk quashed Sunderland's hopes of three points and a first clean sheet in 15 Premier League games with his late leveller.
Here's what we learned from the draw:
Sunderland will go down unless they start keeping clean sheets:
With the seconds counting down it appeared Sunderland had finally done enough to keep their first clean sheet since November.
But van Dijk's late equaliser left the sold-out away end devastated.
Sunderland had defended well, Younes Kaboul and Lamine Kone impressing, keeping Pelle, Tadic & Co quiet.
But they couldn't hold on, with Tadic given too much space to pick out van Dijk.
This week alone Sunderland have thrown away at least four points.
With just nine games left, they must start keeping clean sheets.
Dame N'Doye didn't impress leading the line:
With just one goal in his last six games, it perhaps, shouldn't have come as too much of a surprise to see Jermain Defoe left out the side.
This was N'Doye's chance to shine in his favoured central role.
But he struggled to impose himself on the Saints defence, doesn't win as many headers as he ought to given his height and didn't threaten Fraser Forster's goal.
Point proved for Defoe after he came off the bench to score but it won't do him any harm to keep him hungry.
Two from Sunderland, Newcastle United and Norwich City with Aston Villa doomed:
Saturday was a key day in the fight against the drop, with Swansea City and AFC Bournemouth giving their chances of safety a significant boost.
Sunderland remain fourth bottom - a point above the drop zone - but they are now eight points behind Swansea in 16th.
The Swans beat Norwich 1-0, while AFC Bournemouth's win over Newcastle puts them within another win of safety.
Realistically, it means Sunderland are now battling it out with Norwich and Newcastle for Premier League survival, with Aston Villa all but down after they were thumped at Manchester City.
Fabio Borini proves his worth:
The Italian's work ethic and sheer willingness to chase every ball are to be admired.
He also had a couple of excellent chances to add to his tally of three goals for the season.
A sublime dipping volley went just over Forster's crossbar, while the England international got down well to block another of Borini's efforts on goal.
Impressive Borini was also fouled by Fonte as he bore down on goal, the defender red carded.
He deserves an extended run in the side.
Enforced two-week break comes at worst possible time:
Sunderland now face a two-week break before the Tyne-Wear derby and after a week of promising performances it has come at the wrong time for Sunderland.
Yes, they threw points away against West Ham United, Crystal Palace and Southampton.
But the performances have been decent, mistakes in giving away cheap goals have been the problem.
Sunderland could do with a game next weekend to get the frustrations of the Saints draw out of their system.
The break may have come at the wrong time but at least it gives Allardyce two-weeks to find a way for this side to keep a clean sheet.
John O'Shea faces a battle to regain place:
The Cats captain was on the bench at St Mary's, not deemed fit enough to start following a calf injury.
But he now faces a fight to get back into the side, with Kaboul - captain for the day - and Kone doing little wrong.
They formed a formidable partnership at the back, with Sunderland defending well.
The defence as a whole just couldn't hold out.
Allardyce has a big decision to make ahead of the Tyne-Wear derby as to whether to recall O'Shea.