The referee blows his whistle for full-time. Arsenal have won 1-0 and will now travel to Brighton in the fourth round of the FA Cup.
Giroud winds down the clock by winning a corner.
Cazorla cuts in from the left and fires a wild effort over the bar. Just one minute left.
Michu can't find space on the edge of the box and Arsenal work the ball away from danger.
There will three minutes of additional time at the end of this match.
Swansea try to battle back but Ki can only knock a pass behind for a goal-kick.
Arsenal are ahead late in this game. They have missed plenty of chances but that won't matter if Wilshere's goal is enough to decide this clash.
GOAL WILSHERE! The goal finally arrives! Wilshere fires home a half-volley from the edge of the box to give Vorm no chance. Good work from Giroud to find the midfielder in space.
More drama from the corner as Giroud sees a powerful volley blocked by Dwight Tiendalli. Arsenal are becoming more frustrated.
Walcott's low effort is knocked away from goal by Vorm. Arsenal collect the ball on the right flank and the resulting cross is knocked behind for a corner.
Arsenal now make a change with Aaron Ramsey taking the place of Diaby.
Arsenal hit the post as Sagna's cross from the right evades Walcott and strikes the far post. Vorm collects the loose ball.
Swansea go fairly close's from the corner as Chico's header at the near post goes narrowly wide.
Szczesny is still alive to the Swansea threat as he tips a Ki effort behind for a corner.
Giroud misses another chance as his low effort from inside the box is easily gathered by Vorm. Frustrating times for Arsenal.
Wilshere's corner from the right is poor and Richards is again able to head clear at the near post.
Coquelin wins a corner as his cross from the right deflects behind off Britton.
Wilshere can't play Cazorla through on goal as his attempted through ball races out of play for a goal-kick.
Wilshere's driven effort from the edge of the box is punched away from goal by Vorm. The Swansea goalkeeper is pretty busy tonight.
Sagna is the latest Arsenal player to fire a shot at goal. This effort from the edge of the area goes high over the bar.
Here's Michu! He replaces Graham at the centre of the Swansea attack.
Walcott manages to create some space but the shot disappoints as he drags the ball wide of goal. The missed chances are adding up for Arsenal.
Giroud turns on the edge of the box but his shot is straight at Vorm. Another save from the Swansea goalkeeper.
Looks like Swansea are getting ready to bring Michu on.
Swansea look for a bit of quiet as they keep the ball at the back. It has been a dangerous few minutes from Arsenal so the away side need to keep it tight.
Arsenal on top again but Swansea can still pose questions on the break.
The resulting corner causes more problems for Swansea as a second effort is cleared off the line. Britton the man to get the credit this time.
A great decision from the referee as he turns down Arsenal's appeals for a penalty. Graham knocked the ball off the line with his chest - not his arm - and the Gunners have a corner. Walcott also saw a shot saved by Vorm.
Another poor corner from Walcott as his effort is cleared by Richards at the near post.
Wilshere charges forward but he is tackled before getting a shot at goal. Corner to Arsenal.
And another Swansea change as Ki takes over from de Guzman in midfield.
Swansea make the first change of the night with Pablo Hernandez replacing Kemy Agustien.
Giroud finds space in the six-yard box but he can only send his header wide of goal. Again the striker should have done better with a chance.
Per Mertesacker and Vermaelen combine to create a slightly nervous moment for Swansea but the away side work the ball away from danger.
Leon Britton knocks Olivier Giroud's cross from the left behind for a corner. Swansea clear the resulting flag-kick.
The corner is cleared and that allows Walcott to break. A very quick run from the forward but he runs the ball out of place just after the halfway line.
Sagna knocks the ball away from Routledge and behind for a corner.
Swansea enjoy some possession after that half-chance to threaten. Still plenty for the away side to feel optimistic about in this clash.
Graham can't find de Guzman free in the area as his pass from the left goes flying out of play for a throw on the opposite flank. Still Swansea threat on the break.
Giroud can't test Vorm as his volley from a tight angle goes wide of the Swansea goal. Arsenal creating quite a few chances now.
Cazorla makes some space on the edge of the box and fires a powerful effort just over the bar. Arsenal have started this half on the front foot.
The forward feels he was pushed by Chico before that shot. He has a point but the referee is quite clear that the advantage was played.
Walcott goes through one-on-one with Vorm but he can only divert his effort wide of goal. Should have done better.
No changes at the break from either side.
The action is back under way.
A few half-time price boosts from Sky Bet. Arsenal to win 2-1 is available at 11/1 and you can get the same price for Swansea to win 1-0. Giroud to score next is 9/2 and Dyer is a 22/1 shot.
That ends the first half. No goals yet at the Emirates so all to play for after the break.
A great save from Vorm right at the end of the half to deny Vermaelen. He used his legs to stop the shot in the centre of the goal.
There will be one minute of additional time.
Sagna's cross from the right is met by Gibbs at the far post. His header creates a problem for Chico in the six-yard box but the defender does well to knock the ball clear.
A bit of frustration for Arsenal as Cazorla's effort fails to test Vorm. Will be interesting to see if the approach from the Gunners changes.
Vorm is alive to a little bit of danger and races out of his goal to knock the ball away from Giroud. The Swansea goalkeeper is always good at dealing with situations like that.
This corner from Walcott is better and Chico is equal to the threat to head clear.
Walcott's effort is blocked to provide more frustration for Arsenal. The forward, despite his poor set-pieces, is the most lively player for the Gunners tonight.
Coquelin runs out of space and the ball goes behind for a goal-kick.
Swansea are keeping men behind the ball to frustrate Arsenal. The Gunners are causing some problems but a bit more is needed.
The corner from the left is worked short by de Guzman but his resulting cross is too long and goes behind for a corner.
Good work from Vermaelen to block Dyer's shot and knock the ball behind for a corner. Swansea continue to produce problems on the break for Arsenal.
Coquelin plays the ball behind Kieran Gibbs and that gives Swansea a throw on the halfway line.
Wilshere's corner from the right is cleared by Bartley after a little bit of a scramble. Swansea's defence holds firm.
Sagna wins a corner as his run down the right is halted by Routledge.
Wilshere finds himself offside in the Swansea box. Correct decision from the linesman.
Swansea enjoy a spell of possession at the back. The Arsenal fans try to offer a bit of support but more is needed from the Gunners.
Diaby catches De Guzman with his arm to bring a break to the play. No action is taken and the Swansea midfielder is fine to continue.
Walcott's free-kick from the left is very poor and goes straight behind for a goal-kick. The forward's set-pieces have been awful tonight.
Arsenal get a free-kick on the left flank as Giroud's cross hits the arm of Bartley.
That chance should worry Arsenal. The hosts have been the better side but Swansea are posing a threat on the break.
Routledge's cross from the left is headed against the bar by Bartley from close-range. He should have scored so that's a lucky escape from Arsenal.
Dyer's low cross from the right is cleared away from danger by Sagna. Swansea are trying to enjoy some joy on the break.
Wilshere's corner from the right is half-cleared to Francis Coquelin on the edge of the box. The midfielder's effort causes Michel Vorm a slight worry but he gathers the ball at the second attempt.
Vermaelen's free-kick deflects off the top of the wall to give Arsenal a corner.
Walcott stumbles right on the edge of the box and goes down after Chico's challenge. The referee takes his time but does give Arsenal the free-kick.
Graham sends a very poor effort wide of Szczesny's near post. No joy for the Swansea striker so far tonight.
Walcott's corner from the left is cleared by Richards at the near post. Poor set-piece from the Arsenal forward.
Abou Diaby's effort from the edge of the box is blocked by Kyle Bartley. Good work from the Swansea defender against his former club.
Thomas Vermaelen stops Nathan Dyer with a strong challenge in the box. The loose ball falls to Wayne Routledge and his progress is stopped by Bacary Sagna.
Swansea now enjoying some possession. Jonathan de Guzman is the man trying to pull the strings.
Giroud can't find Walcott in the box. The ball goes behind the forward and Swansea clear.
Arsene Wenger will be quite happy with how this match is going. Arsenal look the more lively and there hasn't been too much from Swansea in attack.
More Arsenal possession. Swansea are organised so no new chances.
Arsenal enjoy another spell of possession. Swansea have Graham alone in attack so they are quite happy to have men behind the ball.
Good start from Arsenal. Walcott looks lively and Giroud is finding plenty of space.
Giroud battles to find space on the left flank and his cross is cleared away by Chico. All Arsenal at the moment.
Giroud is once again in space in the box and his shot goes wide of the near post. The striker should be doing better with these efforts.
Walcott's cross from the right finds Giroud but the striker can only send his header wide of the near post.
Santi Cazorla can't find Olivier Giroud and the ball goes behind for a goal-kick.
Swansea keeping the ball at the back. Chico is forced to clear after Walcott puts him under some pressure.
Danny Graham finds some space way outside the Arsenal box and sends a wild effort well wide of Wojciech Szczesny's left hand post.
Theo Walcott's attempt to find Jack Wilshere in the box is cut-out by Ashley Richards.
The action has started. The winner of this tie travels to Brighton in the fourth round of the FA Cup.
The players are out on the pitch.
Getting closer to kick-off now. Just five minutes until the game begins.
Matt Banks e-mails in to say: "Arsenal will have their work cut out tonight against a talented Swansea outfit. They will need to defend better than they did on Sunday & press Swansea from the off. This is our best chance of a trophy so really hoping for an early Gunners goal to settle the nerves."
Here's some news on the odds for the game from Nigel Askham of Sky Bet: "Having drawn 2-2 at the Liberty Stadium, Arsenal are strongly backed at 2/7 to qualify for the fourth round and are 8/15 to pull off the victory in 90 minutes. The Swans are out at 9/2 or 5/2 to qualify via extra-time or penalties. If you fancy home goals its 9/2 for Theo Walcott and Olivier Giroud to both find the net."
A bit more info about the teams: Olivier Giroud returns to the starting line-up for Arsenal. Theo Walcott looks set to switch back to the right flank, with Lukas Podolski dropping to the bench, while Per Mertesacker comes in for suspended defender Laurent Koscielny after his red card against Manchester City on Sunday. Swansea won 2-0 here in the Premier League on December 1, but make six changes from their last match, with striker Michu, who hit both goals in that victory, on the bench as Danny Graham leads the attack.
The Swansea team is: Vorm; Richards, Chico, Bartley, Tiendalli; Britton, Agustien, de Guzman; Routledge, Graham, Dyer. Subs - Tremmel, Monk, Davies, Ki, Shechter, Hernandez, Michu
The Arsenal team is: Szczesny, Sagna, Mertesacker, Vermaelen, Gibbs, Coquelin, Wilshere, Diaby, Cazorla, Walcott, Giroud. Subs - Mannone, Jenkinson, Santos, Ramsey, Oxlade-Chamberlain, Arshavin, Podolski
Hello and welcome to our live coverage of the FA Cup third round replay between Arsenal and Swansea at the Emirates. E-mails can be sent to email@example.com as we get ready for kick-off at 1930 GMT.