Postpublished at 82 mins
Bournemouth 0-3 Southampton
Any more goal contributions from Nathan Redmond today?
Listen to 5 Live and local radio commentary, plus watch in-play clips
Djenepo slots in after superb play by Redmond, who then adds second and third goals
Southampton last reached semi-finals in 2018, losing to eventual winners Chelsea
Semi-final draw on BBC One on Sunday, at half-time in Leicester v Man Utd (17:00 GMT kick-off)
Emma Sanders
Bournemouth 0-3 Southampton
Any more goal contributions from Nathan Redmond today?
Bournemouth 0-3 Southampton
Che Adams is almost in!
He sneaks in behind on the right, is slipped through but his touch is heavy as he races into the box and Asmir Begovic gathers it in.
Bournemouth 0-3 Southampton
Ibrahima Diallo pulls his strike wide on the corner.
Bournemouth 0-3 Southampton
Arnaut Danjuma forces a save from Fraser Forster from a tight angle on the left side of the box.
Southampton immediately go up the other end through Stuart Armstrong - who won't stop running - but his cut-back for Nathan Redmond is steered behind for a corner.
Bournemouth 0-3 Southampton
Here come the Southampton changes.
Jan Bednarek, on a yellow, is off for Jack Stephens. Jannik Vestergaard, also just booked, is replaced by Mohammed Salisu.
Gavin Kilkenny replaces Phillip Billing for Bournemouth.
Bournemouth 0-3 Southampton
HAT-TR...
Soooooo close. Nathan Redmond almost has his third. Would have been the pick of the bunch too.
Stuart Armstrong just runs and runs with it - evading one, then two, then three challenges before poking it through to Redmond on the slide in the box.
Redmond sees a gap and curls it towards the far right corner. INCHES wide.
Bournemouth 0-3 Southampton
Sealed the deal.
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Kyle: Very impressive performance from Southampton minus Danny Ings in a derby away from home. 3 up and they could be 5 up. Bournemouth have to be careful they don't get hammered by 5 or 6 as that could affect their league form moving forward.
Bournemouth 0-3 Southampton
Jannik Vestergaard faffs on the ball and gets it nicked off him by Phillip Billing. He holds him back to stop him breaking away and takes the yellow.
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Darren: Diabolical all round display from AFC Bournemouth. Absolutely shambolic defending and no pride to wear the shirt. Once in a lifetime opportunity to get to the Semis and they've blown it in style !
Scathing, Darren.
Bournemouth 0-3 Southampton
Stuart Armstrong has come close a few times today too - including that strike which hit the post in the build-up to Nathan Redmond's second goal.
He has a go from long range again and catches it nicely, forcing a smart low save from Asmir Begovic.
Bournemouth 0-3 Southampton
Stuart Armstrong floats it over to Kyle Walker-Peters on the right. He cuts it back to James Ward-Prowse who volleys it into the ground.
It bounces up awkwardly - there's appeals for handball - before Asmir Begovic gets his gloves on it under pressure from Che Adams.
Bournemouth 0-3 Southampton
Moussa Djenepo and Che Adams link-up just outside the box. Nathan Redmond makes a run in behind and Adams tries to poke it through but Steve Cook gets in the way.
Bournemouth 0-3 Southampton
Chris Mepham is on for Bournemouth. Diego Rico is off.
No changes for Southampton yet.
Bournemouth 0-3 Southampton
Tony Pulis
Former Stoke manager on BBC Radio 5 Live
The game has really fallen away from Bournemouth - that third goal really kills it in lots of respects so it's difficult now. They've got to keep their heads and try and keep doing things properly.
3-0 down against a team with good quality and good counter-attacking quality is tough, you don't want it to become four, five or six by chasing the game stupidly. Very difficult situation.
Bournemouth 0-3 Southampton
Nathan Redmond has scored his first brace for Southampton since April 2019 against Wolves.
Bournemouth 0-3 Southampton
Moussa Djenepo and Jack Wilshere clash heads slightly as they go up for an aerial battle in midfleld so they are just checking them over.
Bournemouth 0-3 Southampton
Very good afternoon for Nathan Redmond. Ralph Hasenhuttl is loving life as well.
Che Adams wants in on the action now though and does enough to win a corner with support from the other goalscorer - Moussa Djenepo.
Bournemouth 0-3 Southampton
Tony Pulis
Former Stoke manager on BBC Radio 5 Live
The disappointing thing is that you sit and wonder whether VAR are going to pull it back again - rather than celebrating and talking about the goal.
It is a brilliant strike though, comes off the post and Nathan Redmond just had very good technique there.
Bournemouth 0-3 Southampton
No VAR check. The goal is 100% a thing!
Now it's game over, surely?