CLOSE!published at 15:50 Greenwich Mean Time 25 January 2015
He's such a threat in the air! Matt Smith beats his man to the ball again and that is some header, power from 15 yards but it floats just wide!
Last chance?
Summary
Arsenal survive late scare to advance
Villa beat Bournemouth 2-1 to progress
West Ham win 1-0 at Bristol City
Watch goals via highlights tab
Fifth-round draw on Monday at 19:00 GMT
CLOSE!published at 15:50 Greenwich Mean Time 25 January 2015
INJURY TIMEpublished at 15:49 Greenwich Mean Time 25 January 2015
THREE MINUTES added on. The West Ham fans are singing that they want to go home. They may be heading back to London with a win at this rate.
Postpublished at 15:48 Greenwich Mean Time 25 January 2015
Phil McNulty
BBC Sport chief football writer"Very impressive first half from Bournemouth. They looked the superior side as the half progressed. Villa - in line with all the recent evidence - look like a team that does not know where its next goal is coming from. Few boos from the home fans."
HALF-TIMEpublished at 15:48 Greenwich Mean Time 25 January 2015
Villa haven't scored. Who would have guessed?
Join the debate at #bbcfacuppublished at 15:47 Greenwich Mean Time 25 January 2015
Allyd Roberts: Shock on the cards at Ashton Gate - the Premier League team is actually winning!
Get involved using #bbcfacup, external on Twitter, text us on 81111 (UK only), or drop us a line on the BBC Sport Facebook, external or Google+ page., external
Postpublished at 15:47 Greenwich Mean Time 25 January 2015
Matt Smith has another header on goal but it's easy for Adrian to hang on to. City still pushing hard but West Ham look solid enough at the back. Andy Carroll helping out as an auxiliary centre-half at times.
Postpublished at 15:46 Greenwich Mean Time 25 January 2015
Former West Ham striker John Hartson
BBC Radio 5 live at Ashton Gate
Image source, AFP"We've seen Diafra Sakho produce moments of brilliance this season and he has provided the difference between these two teams here today. Up until the goal the Bristol City 'keeper hadn't really been troubled, and City had two shots cleared off the line in the first half. They have played really well today and I am sure Steve Cotterill the manager will be really proud. But there is still time to play yet."
Postpublished at 15:45 Greenwich Mean Time 25 January 2015
West Ham are four minutes away from round five. With teams at the top of the Premier League falling by the wayside how far could the Hammers go?
Postpublished at 15:45 Greenwich Mean Time 25 January 2015
Image source, ReutersAt Villa Park, Bournemouth continue to play the more composed and controlled football as we approach half-time.
Postpublished at 15:43 Greenwich Mean Time 25 January 2015
City are not taking this lying down, Joe Bryan shoots well wide from range before Matt Smith heads agonisingly close! Ah, the whistle had gone - it was a foul. Great effort though.
Join the debate at #bbcfacuppublished at 15:42 Greenwich Mean Time 25 January 2015
Dean Ellinor: The team now ahead really shouldn't be! Bristol City have been the better team all game.
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SUBSTITUTIONpublished at 15:41 Greenwich Mean Time 25 January 2015
That's the difference, top strikers convert their chances. Bristol City throw on Kieran Agard as the West Ham fans sing about going to Wembley...
Postpublished at 15:40 Greenwich Mean Time 25 January 2015
Former West Ham striker John Hartson
BBC Radio 5 live at Ashton Gate"A brilliant header from Diafra Sakho. That is why he was brought on - to make the difference. Sakho rose to head the ball in off the underside of the bar, right on the back post. But it was great play from Andy Carroll to get the cross in. It looked like he was going nowhere."
GOALpublished at 15:39 Greenwich Mean Time 25 January 2015
The substitute strikes! Diafra Sakho has West Ham ahead but he owes it all to Andy Carroll. Carroll bulldozes down the right-hand side, power and poise in unison before clipping the ball over on the run. The cross is perfect for Sakho to attack at the back post and heads in off the underside of the crossbar.
Is that the winner?
Image source, Getty ImagesPostpublished at 15:38 Greenwich Mean Time 25 January 2015
West Ham's subs have breathed some life into them and Morgan Amalfitano this time takes aim from 25 yards, a dipping strike which calls Frank Fielding into action. Comfortable save but a fine hit.
Vote nowpublished at 15:37 Greenwich Mean Time 25 January 2015
You can now vote for the FA man of the match award by voting at the top of the page. Kevin Kilbane has given you three options to choose from and the vote closes on 90 minutes. Terms and conditions can be found here.
Postpublished at 15:37 Greenwich Mean Time 25 January 2015
Phil McNulty
BBC Sport chief football writer"Bournemouth growing in confidence and demonstrating it with their composed passing game. Villa have not been able to get Christian Benteke into the game and Bournemouth manager Eddie Howe will hope the longer this stays goalless the more it will play on Villa's frayed nerves. The home crowd is very quiet."
YELLOW CARDpublished at 15:37 Greenwich Mean Time 25 January 2015
Kevin Nolan's touch gets away from him and he slides in to recover but can only catch a City defender high and late. Booked.
Just 12 minutes left at the Gate - it looks like a replay - especially as Luke Ayling heads a presentable chance over the bar!
Text us on 81111published at 15:35 Greenwich Mean Time 25 January 2015
Jo, Brighton: So excited about the game. I live in Brighton but am a huge Gunners fan so it's win win whatever today. Think Brighton will chase hard and just miss it. 3-2 to Arsenal.
Daniel, Darlington: Barring Santi Cazorla that's a full-strength Arsenal team, but if yesterday taught us anything it's that that means nothing. Come on Brighton!
Get involved using #bbcfacup, external on Twitter, text us on 81111 (UK only), or drop us a line on the BBC Sport Facebook, external or Google+ page., external
GREAT SAVE!published at 15:34 Greenwich Mean Time 25 January 2015
Image source, Getty ImagesThings are heating up. At Villa Park, Bournemouth midfielder Eunan O'Kane slams in a left-footed drive from range and Shay Given has to make a one-handed stop. Harry Arter then sees his shot deflected into the side-netting and the Premier League side are on the rack.