Brighton snatched a point with a stoppage-time penalty.
Referee Anthony Taylor adjudged Duffy to have been fouled by James Ward-Prowse and Glenn Murray made no mistake from the spot to force a 2-2 draw.
Re-live all the action below:
Live Updates
22:03
That is all from us here tonight.
I've been Harry Latham-Coyle for The Independent - thank you for joining me.
22:01
A stalemate on the South Coast, but that second-half was anything but stale.
The first half was a rather drab affair lit up by Pierre-Emile Højbjerg's superb low strike from 30 yards out, but the game came to life after the interval.
Danny Ings put Southampton firmly in the driving seat with a calmly-taken penalty after he was fouled, but Shane Duffy's swift reply gave Brighton renewed energy.
Chris Hughton's side looked a danger from set-pieces throughout and both their goals came via Duffy, the first a header from a lovely whipped ball by Anthony Knockaert and the second coming after the defender was adjudged to have been pulled down late on.
Glenn Murray stepped up to score his 98th Brighton goal and for the second game in a row the Seagulls have secured a draw after falling two goals behind.
21:50
90+3 minutes
Close! Bertrand, from the right hand side of the box, opts to try and stick it into the far corner rather than go over the wall.
Mathew Ryan reacts well and is able to palm it away.
21:49
90+2 minutes
Another twist? Jurgen Locadia compounds an error, giving the ball away and then conceding a free-kick withing striking distance.
Ryan Bertrand stands over it..
21:46
PENALTY!
Shane Duffy is dragged down from the resulting corner...
21:46
A teasing delivery again from Knockaert, a downward header bounces awkwardly in front of him but Alex McCarthy somehow manages to parry it over the bar.
89 minutes
Top save!
A teasing delivery again from Knockaert, a downward header bounces awkwardly in front of him but Alex McCarthy somehow manages to parry it over the bar.
But hold on...
21:45
89 minutes
Anthony Knockaert's shot is deflected over. Another corner.
21:44
87 minutes
What are you doing Mathew Ryan? His clearance is awful and the goalkeeper is fortunate that Gabbiadini can't hook his effort on target from far out. Ryan was out of the picture at left-back after chasing a ball.
Time running out.
21:41
85 minutes
Nothing comes of the corner. Southampton clear into Brighton's half and earn a throw.
Manolo Gabbiadini softly returns favour and then a foul from Wesley Hoedt gives Brighton an opportunity to lump the ball into the box from half-way.
21:40
83 minutes
A corner for Brighton.
Southampton make their final change, Steven Davis on to provide a steadying hand. Off goes Danny Ings. Another strong display from the striker, and good to see him fit and firing.
21:36
80 minutes
Plenty of attacking options on the pitch for the visitors as they press for an equaliser. A clever flick from Jahanbakhsh is just wide.
21:33
75 minutes
Changes afoot. Three of them in fact.
Southampton introduce Manolo Gabbiadini and James Ward-Prowse for Mohamed Elyounoussi and Shane Long.
Brighton make another attacking alteration, with powerful forward Jurgen Locadia on for Yves Bissouma.
21:29
A certain penalty...
21:28
70 minutes
A first change for Brighton. Chris Hughton brings on Alireza Jahanbakhsh for Solly March. The Iranian scored 21 times in the Eredivisie last season and now would be a welcome occasion for his first Premier League goal.
21:26
69 minutes
It is opening up, this one.
Nathan Redmond again threatens with a run into the box but opts to shoot when a square pass was perhaps a better option.
