Postpublished at 83 mins
Spurs 2-2 Southampton
Spurs are playing a bit better now. They're pushing for a winner.
Ndombele's shot deflects off Stephens for opener
Ings hits bar from close range for visitors, before Long levels
Ings bends home from just inside area after Redmond break but Moura levels
Son puts hosts back ahead from spot after being brought down
Ward-Prowse carried off on stretcher with serious-looking knee injury
The winners will entertain Norwich in the fifth round
Listen to BBC Radio 5 Live commentary from 19:45 GMT
Emlyn Begley
Spurs 2-2 Southampton
Spurs are playing a bit better now. They're pushing for a winner.
Spurs 2-2 Southampton
On comes Che Adams, who has scored no goals in 23 games since a £15m move from Birmingham. This would be a good time to break that duck. Shane Long is replaced.
Spurs 2-2 Southampton
Emma Hayes
Chelsea Women manager on BBC Radio 5 Live
Wow. What a goal from Lucas Moura! It's the first time that Dele Alli has combined with Moura but all the credit needs to go to Harry Winks, Moura has almost dropped into a 10 position and it was wonderful feet by him. What a strange game.
Spurs 2-2 Southampton
Southampton striker Shane Long is getting some treatment on the touchline. I didn't see what happened to him. Che Adams is getting ready.
Spurs 2-2 Southampton
I didn't see that one coming to be honest. Extra time? Penalties?
Lucas Moura
Spurs are level!
Lucas Moura plays the ball forward to Dele Alli, who gives it back to the Brazilian and he steps past Jannik Vestergaard before blasting the ball into the bottom corner from 18 yards.
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London Money: If Southampton had show their recent form from the start of the season they'd be pushing the top 5!
Southampton are a good side, the manager deserves a lot of credit for turning things around since they lost 9-0 at home to Leicester. But really Spurs are once again being dominated at home, this time to Southampton. Not sure if this will continue to wash with Spurs fans.
Paul, Luton
Spurs 1-2 Southampton
Better from Spurs and they have a corner won by Ryan Sessegnon.
Spurs 1-2 Southampton
Emma Hayes
Chelsea Women manager on BBC Radio 5 Live
Southampton deserve that! It's a brilliant counter-attack that had all the precision that Spurs lack. I cannot believe how naive Tottenham have been defensively. Winks and Son failed to win the ball or bring Redmond down and Tanganga gets far too narrow and allow Ings to get back inside and it's a lovely finish. Both Son and Winks were too passive.
Spurs 1-2 Southampton
Hugo Lloris just avoids conceding a penalty. Ryan Bertrand runs into the box and tips it around Lloris, who just pulls his arms away in time before bringing Bertrand down - and the ball runs out of play.
Danny Ings
Southampton lead and they fully deserve it.
Gedson Fernandes crosses the ball into Southampton's box and Shane Long heads it away.
It reaches Nathan Redmond, who takes on two players and carries the ball 50 yards before sliding in Danny Ings. Spurs players back off Ings and he guides it past Hugo Lloris from 16 yards.
Excellent goal.
THIS IS A COUNTER ATTACK!
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David Freedman: Southampton look the most likely to score based on the flow of play, but as we know that doesn’t win you the game. Watch for a quick Spurs break and game over.
Jose Mourinho reminds me of the the last days of Brian Clough in the early to mid 90’s. Great manager in his day, but his 70’s ways were so out of touch by the end it was embarrassing to watch.
Lee, London
Spurs 1-1 Southampton
That would have been bad timing for Emma Hayes if he'd scored here. Eric Dier shoots from 20 yards but it's blocked wide for a corner.
Spurs 1-1 Southampton
Emma Hayes
Chelsea Women manager on BBC Radio 5 Live
It's been so impressive to watch live the amount of work Southampton players have put through. Out of possession, in particular, they have not let Tottenham settle at any point. We mentioned Harry Winks earlier but Eric Dier, you don't even know he's playing in this game.
Spurs 1-1 Southampton
Son Heung-min looks in some pain. Jack Stephens stands on his arm (by accident I think) after a clash.
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David NicholsonHirst: Spurs look poor with no idea....Pochettino is still a free agent, correct?
Ed Franklin: Well this is continued awfulness under Mourinho. You could easily believe Spurs are a third tier team playing a Premier League club.
Spurs 1-1 Southampton
Spurs want a penalty as Serge Aurier blasts the ball towards Jannik Vestergaard's arms from about six inches. That would have been very harsh.
Spurs 1-1 Southampton
Southampton make a change now - Stuart Armstrong replaces Sofiane Boufal in midfield.
Spurs 1-1 Southampton
Southampton have had 14 shots - six on target. Spurs have had five - one on target.