Last Updated: 06/10/13 5:53pm
Koscielny and Long collide and the latter wants a penalty, but it's a goal kick to Arsenal. The visitors then have one last chance to break but nothing comes of it and that's full-time.
Another cheap free-kick given away by Arsenal and we're within a minute of a draw here, which would be a fair result.
Wilshere is adjudged to have pushed Ridgewell and that buys West Brom some valuable time, which they make full use of with Myhill strolling out to take the free-kick.
Superb interplay from Arsenal but Wilshere is forced to cross on his weaker foot and Myhill collects. Four minutes of added time await.
Jenkinson again attacks down the right but it's well-defended and a goal kick. The break allows Amalfitano to make way for Brunt.
Rosicky produces a delightful touch to release Flamini, but the Frenchman can't produce a finish to match and his shot deflects tamely to safety.
Brilliant from Mulumbu, who beats Arteta to the ball. However, the resulting counter ends when Morrison can't quite keep the ball in play.
Long wins a header and it falls to Amalfitano, who volleys wide from range. Less than five minutes of normal time remaining.
The referee continues to allow play to flow, this time to the chagrin of Giroud who thinks he's been fouled on the edge of the box.
Jenkinson has done well going forward but another cross is just behind his intended target. Arsenal get it back quickly as Long is adjudged to have handled the ball.
Ozil gives it away cheaply as Arsenal threaten to break and Jones does very well to clear under pressure.
Gibbs looks to have pushed Long and a foul is given, the only surprise being the time it takes the referee to decide to give it. The break in play allows West Brom to make a change, with Sessegnon replaced by Morrison.
Ozil gets into the box down the right and cuts it back to Wilshere, but just as he's about to shoot Mulumbu catches up and makes what looks a fine tackle. The referee agrees and replays confirm he's right to.
Exceptional goalkeeping from Myhill after a fine ball from Wilshere puts Giroud through. The West Brom stopper got down low to prevent what looked a certain goal.
West Brom have had six corners and this is perhaps the worst of them, failing to beat the near-post man. West Brom come again though and have Arsenal penned in for now.
Lovely work from Mulumbu and the ball eventually finds it way to Jones, who forces a save from Szczesny with a powerful strike from distance.
Jenkinson is back on and appears fine. Arsenal are on the attack once more down the left and Myhill has to punch clear. It goes only as far as Ozil, who lofts a ball to Giroud only to see the striker volley wide.
Jenkinson goes down under a challenge from Long and it's an awkward fall which sees the Arsenal man require attention.
Anelka makes way for Long. Solid shift from the West Brom striker but he did miss a fine chance to put his side 2-0 ahead.
Rosicky beats Mulumbu to the ball but the West Brom man gets his revenge and plays in Sessegnon, who almost releases Anelka only to find Koscielny blocking his path.
We're approaching halfway through the second-half and West Brom appear to be preparing a change, with Long perhaps the man poised to join the action.
To their credit West Brom are back on the attack, with Amalfitano's ball causing problems for the Arsenal defence.
Wilshere is the pantomime villain, his every touch resulting in boos from the crowd. His ball finds Giroud offside.
Replays suggest that Wilshere effort was helped by a little deflection, but it was a goal of quality which came about thanks to a swift Arsenal break. West Brom had looked comfortable but it's game on now.
GOAL! Wilshere! Anelka again threatens down the right but his cross is cut out and Arsenal break. Giroud plays it to Rosicky, who lays it off to Wilshere and his first-time strike from distance finds the net. Spectacular finish.
Yacob has his eye in, or so he thinks, after that first goal for the club, and has a go from range. It's wide.
Arsenal have upped the tempo a little but first Rosicky then Gibbs are careless and give the ball away. West Brom break but Jenkinson can head clear.
Rosicky is involved immediately in a move which sees claims for an Arsenal penalty waved away correctly. Arsenal come again, this time down the right, before the ball breaks to the Czech midfielder but he can only blast over.
Berahino's persistence pays off as he beats Jenkinson to the ball before winning free-kick, which allows Arsenal to bring on Rosicky for Ramsey. Slightly surprising it's him and not the booked Wilshere who makes way.
Amalfitano gives away possession very cheaply and that allows Ozil to move into the box before finding Flamini, but his shot is blocked and deflects high into the air for Myhill to collect.
Gibbs is furious as he's adjudged to have fouled Sessegnon. Amalfitano delivers and it falls to Berahino, whose shot is weak and straight at Szczesny.
Arsenal are enjoying plenty of possession here but if West Brom keep their shape as well as they have so far a moment of magic may be required to break the deadlock.
Ozil's free-kick is clipped towards Koscielny but he's adjudged to have fouled Jones and it's a cheap free-kick for West Brom.
Olsson gives it away cheaply and eventually pays the price, diving in to get ahead of Giroud but catching the Arsenal man and earning himself a booking.
It should be 2-0 to West Brom. Anelka finds himself in acres of space - despite appearing to be offside - and takes his time before rolling the ball past Szczesny but wide of the post. Huge let-off for Arsenal.
Sessegnon again drifts to the left and wins a free-kick which again sees Olsson and McAuley join in. Szczesny punches clear and Arsenal break, but a cross towards Giroud is collected by Myhill.
Jones shows his attacking ability once more in getting to the byline before crossing low, but Koscielny is there to clear the danger.
It's been a lively start to the second-half and no sign yet that West Brom are going to try to sit on their lead.
Arsenal break swiftly and Wilshere finds space in the area, blasting over under pressure from Jones. Arsenal then come again but Jenkinson's cross is behind Giroud.
A hurried through-ball from Koscienly goes through to Myhill before Yacob finds Berahino. His cross is perfect, right into Anelka's stride, but from seven or eight yards out he fails to connect and Arsenal get away with it.
West Brom are now 10/11 to win the game with Sky Bet, who go 9/4 the draw and 100/30 Arsenal. Their Price Boosts include Arsenal to win 2-1 at 8/1, Giroud to score next at 5/1 and West Brom to win 3-0 at 33s.
So, 1-0 to the hosts at the break and they probably just about deserve it for that spell of pressure which resulted in their goal. Arsenal have struggled to find space in the final third and a 13th successive away win looks a long way away right now.
Chaos in the West Brom box as Ramsey forces Olsson into a mistake. West Brom escape unpunished though and that's half-time.
Goalscorer Yacob is down for some time after what was a painful-looking challenge from Wilshere, albeit an apparent attempt to win the ball.
There are three added minutes and the first of them sees Arsenal resume control of play, but West Brom continue to hold their shape and gaps are proving hard to find. Wilshere is booked for a late tackle.
Arsenal hadn't looked in any real trouble from set pieces until that point and Wenger will be annoyed that they've given Yacob so much space there. West Brom are buzzing though and are after a second, Arteta being forced to hack clear another cross.
GOAL! Yacob! The corner is poor but Amalfitano is given another chance to cross by Mulumbu, and this one is excellent, finding an unmarked Yacob who nods past Szczesny with an excellent header - that's his first goal for the club.
Good stuff again from West Brom as Amalfitano goes past Wilshere and crosses towards Sessegnon. They eventually win another corner and Olsson and McAuley are forward for it.
Flamini gives away a cheap free-kick deep inside the Arsenal half and Amalfitano will take it. His cross is deep and Szczesny goes down under heavy pressure, but again the referee is having none of it and Arsenal scramble a clearance.
A quick run of passes sees Wilshere free Gibbs down the left and his cross is put behind for a corner. Ozil takes it and it breaks to Ramsey, whose shot forces a good save from Myhill.
Vital header from Arteta as McAuley looked set to nod home from close range only to be denied. Giroud then does well to hold it up before Wilshere spreads it to Ramsey. He, Ozil and Flamini exchange passes but West Brom are well organised and Arsenal have to start again from deep.
Wilshere is again on the floor as a trio of West Brom players surround him before Anelka spreads the play to Sessegnon, who wins his side a corner - their third of the game.
Yacob tracks back to double-up on Giroud with Olsson and it pays off. He then finds Mulumbu but his ball is poor and Arsenal break. Wilshere is blocked by Olsson but the referee thinks he's gone down too easily and waves play on.
Koscielny nips in to tackle Sessegnon and Arsenal break, Giroud doing really well to control a tricky ball before ambitiously shooting from 30 yards. It's saved comfortably by Myhill.
There are some challenges flying in now and Berahino is furious with the referee having gone down under a robust challenge but been given nothing.
Wilshere is back on but a ball from Gibbs fails to find him and Sessegnon attacks down the right, beating two Arsenal players before falling to the floor only to be told to get up by the referee.
Ramsey looks for space in the box but has to concede defeat and go backwards, eventually losing the ball before Ridgewell clears deep into the Arsenal half.
Wilshere looks uncomfortable as he briefly leaves the field with an eye injury. It looks like he'll be fine to continue, though.
Jones advances down the left and plays in Anelka, but the West Brom striker is offside and it's a chance for Wilshere to receive treatment having been caught when losing the ball.
West Brom claim for a foul throw but the assistant referee shakes his head. However, Wilshere loses out again and Arsenal are briefly outnumbered before Ramsey tracks back to dispossess Berahino.
Berahino comes deep to get involved but loses out and the game is developing a familiar pattern, with Arsenal slowly building from defence and looking for gaps.
Wilshere goes down but no foul says the referee. Flamini then confidently tricks past Anelka and sets in motion an attack which ends when Jenkinson's attempt at a cross screws right off his boot and into the crowd.
Amalfitano hoists clear but just as his side look threatening an attempted back-heel goes astray and Arsenal are back in control.
Mertesacker wins a header and Arsenal build again, Ozil darting inside to free up space and then briefly threatening to get in behind. Jones gets there first and it's a corner.
Jenkinson again makes ground on the right before winning a throw. Arteta, Ozil and Wilshere then exchange a nice trio of passes before Wilshere shoots wide from range.
Amalfitano is down for a while but he's fine ultimately and play resumes, with Arsenal knocking the ball across the back.
Amalfitano goes down but the referee plays advantage before eventually going back to book Flamini. Replays show he was right to do so.
The corner is too deep and Arsenal break through Ozil, who drifts inside before picking out Giroud. His header back across goal is cleared but Arsenal come again and McAuley does really well to get a toe to a ball which Giroud was about to strike.
Jenkinson fouls Berahino and West Brom take it quickly, Olsson bursting forward before finding Ridgewell, whose cross is knocked behind by Gibbs with Amalfitano lurking. Corner.
Arsenal are beginning to control possession and Jenkinson takes the opportunity to expose space provided by a neat spell of passing. His run is stopped by Ridgewell, though, and Olsson eventually clears.
Ozil again demonstrates how dangerous he is when allowed time and space to pick a pass, releasing Gibbs who charges into the area before firing over. That was a real chance for the visitors.
Sessegnon bursts forward with a 30-yard run which ends with Jones crossing deep into the Arsenal box. Szczesny comes out and collects well.
Better from Arsenal as Ozil finds Ramsey, who attempts to play in Flamini but finds his pass cut out by Olsson.
Wilshere loses out to Amalfitano as West Brom continue their lively start. The Arsenal midfielder concedes a free-kick which is wasted as Sessegnon is offside.
Amalfitano looks lively and Koscielny is called in to clear after he spins past Gibbs. The ball eventually breaks to Berahino and his deflected shot produces a fine save from Szczesny.
McAuley passes to Jones and he plays a decent ball over the top for Anelka, but the former Arsenal striker can't keep it in play and Arsenal have a throw.
Giroud tries to turn 30 yards from goal after a ball from Koscielny and Yacob fouls him. It's a long way out but Ramsey has a go, his shot sailing high and wide.
Anelka flicks through to Sessegnon and Koscielny does very well to hold him off and turn, before the referee blows for a free-kick to Arsenal.
Mulumbu concedes a free-kick on halfway with a foul on Mulumbu. Eventually Arteta finds space 25 yards out and hits a strong shot which might've caused Myhill problems but for being deflected wide by Giroud.
Amalfitano switches flanks to find space but his ball to Sessegnon is over-hit and goes out for a goal kick.
Ozil exchanges passes with Jenkinson and Ramsey before finding Arteta. He switches the attack as Arsenal probe left and right in search of an opening. The move breaks down as Giroud attempts a backheel to Ramsey.
This has the makings of a good game with West Brom looking just as comfortable as Arsenal on the ball. Mulumbu finds Amalfitano and he in turn puts through Anelka, but his cross is blocked comfortably by Koscielny.
Sessegnon tries to find Berahino but it almost breaks to Jones, who finds himself right on the edge of the Arsenal area. Gibbs steps in to pass to Szczesny who can clear. Arsenal counter but Ridgewell heads back to Myhill to relieve the danger.
Giroud heads clear and then joins in the Arsenal counter, but his clipped cross is too long and eventually Olsson wins a throw-in for his side under pressure from Flamini.
Sessegnon is camped on the left early on and does well to dance inside Jenkinson before finding Ridgewell, whose cross is put behind by Mertesacker for a corner.
Arteta gets an early touch and finds Ozil, who picks out Wilshere on the left. He's joined by Gibbs but the door is closed and Arsenal eventually give it away to Anelka.
Ramsey has started the game on the right but we can probably expect the Arsenal midfield to chop and change roles. So far it's an assured start from the visitors with West Brom forced to close them down in attempt to gain possession.
Jenkinson bursts down the right and reaches the byline but his cut-back is easily collected by Myhill.
Mulumbu tries a shot straight from the kick-off, an ambitious idea but one which didn't work out and Arsenal are quickly in control of the ball.
Much has been made of Arteta's inclusion which would appear to mean Ramsey will be playing from wide, but what about Sagna's enforced absence? West Brom will be looking to get at Jenkinson I'm sure.
Dominic expects a convincing win for the visitors. He says: 'Should be an easy game. 4-0 Arsenal! COYG!' Any West Brom fans care to disagree?
Niall writes: 'Wenger made the right choice with a defensive side. He knows Arsenal will have to deal with Amalfitano and Sessegnon coming through the middle. Good choice from the boss.'
'Rosicky just came back from a long injury so I give him a break today,' says Wenger, who praises his side's consistency and puts their away record down to that. 'Momentum is vital,' he adds, expressing his desire to keep it going into the international break.
Ryan, on the other hand, is very confident of an away win: 'I predict 5-1 Arsenal if we play the same way as we did against Napoli.'
Daniel isn't convinced by Arsene Wenger's team selection. He writes: 'As an arsenal fan, I don't think that picking starting Arteta was the right move. Playing a naturally wide player and Ramsey playing from deep seemed to be working for us.'
Sky Bet make Arsenal 7/10 favourites to secure yet another away win, with West Brom 4/1 and the draw 14/5. Among their Price Boosts is Giroud to score first at 5/1, Arsenal to win 3-0 at 18/1 and West Brom to win 2-1 at 16/1.
West Brom: Myhill, Billy Jones, McAuley, Olsson, Ridgewell, Yacob, Mulumbu, Amalfitano, Sessegnon, Anelka, Berahino. Subs: Popov, Morrison, Rosenberg, Long, Brunt, Lugano, Luke Daniels
Arsenal: Szczesny, Jenkinson, Mertesacker, Koscielny, Gibbs, Arteta, Flamini, Ramsey, Ozil, Wilshere, Giroud. Subs: Vermaelen, Monreal, Fabianski, Bendtner, Miyaichi, Gnabry, Rosicky.