Alexandre Lacazette. Assist by Aaron Ramsey (Arsenal)
89'
GOAL!!! ARSENAL
Pierre-Emerick Aubameyang plays in the overlapping Aaron Ramsey, who adjusts his feet to pull the ball back to ALEXANDRE LACAZETTE. The striker easily ghosts away from Andy Carroll with a drop of the shoulder and finds the net from eight yards. That's six goals in six games for the in-form Lacazette.
9'
KOSCIELNY GOES CLOSE
Granit Xhaka whips in a corner from the left-hand side, and Laurent Koscielny jumps above Cheikhou Kouyate to power a header just two yards wide of the near post. That looked in all the way.
88'
Substitution
Calum Chambers (on). Danny Welbeck (off). (Arsenal)
88'
SUBSTITUTION
Danny Welbeck has had a decent game today and receives a justified ovation as he makes way for Calum Chambers, Arsene Wenger choosing to shore up his defence for the last few minutes.
87'
Yellow Card
Marko Arnautovic (West Ham United)
87'
YELLOW CARD
A frustrated-looking Arnautovic barges Aubameyang off the ball with his shoulder before he gets truly level, earning himself a booking.
86'
Substitution
Andy Carroll (on). Arthur Masuaku (off). (West Ham United)
86'
SUBSTITUTION
Andy Carroll is thrown on for a few minutes of probable route one football.
85'
Goal
Alexandre Lacazette. Assist by Pierre-Emerick Aubameyang (Arsenal)
85'
GOAL!!! ARSENAL
The floodgates are open now. Patient approach play from the Gunners sees Danny Welbeck pass short to Pierre-Emerick Aubameyang, who in turn rolls it to the waiting ALEXANDRE LACAZETTE. The resulting shot from an angle flies through Aaron Cresswell's legs, taking enough of a deflection as it does so to give Joe Hart no chance of stopping it.
82'
Goal
Aaron Ramsey (Arsenal)
82'
GOAL!!! ARSENAL
What a sickener for West Ham. AARON RAMSEY sends a seemingly harmless cross in from the left flank, and Declan Rice inexplicably ducks rather than heading it away, bamboozling Joe Hart and allowing the ball to bounce into the far corner of the net. The Hammers pair argue fiercely as the ball is punted back upfield, almost as if Rice thought he heard a shout.
79'
VINTAGE HART
Hart pulls off a vintage save, springing to his left to somehow claw the ball around the post as Danny Welbeck curls a beautiful shot towards the corner of the net from 18 yards.
77'
HOME ADVANTAGE
The hosts are massing around the edge of the West Ham box and look by far the likelier side to win this at the moment.
74'
Yellow Card
Shkodran Mustafi (Arsenal)
74'
YELLOW CARD
Shkodran Mustafi knocks over Hernandez as he stretches a leg around the side of the striker to poke the ball away, prompting something of a harsh booking.
72'
SUPER SAVE
Xhaka spots gap 20 yards from goal and arrows a low effort across Joe Hart, who has to dive full-length to tip it around the post.
70'
Substitution
Pierre-Emerick Aubameyang (on). Alex Iwobi (off). (Arsenal)
70'
SUBSTITUTION
Arsene Wenger introduces Pierre-Emerick Aubameyang for Iwobi in an effort to regain the attacking impetus.
67'
ANTICLIMAX
A West Ham corner is headed out only as far as Aaron Cresswell, who looks to recycle it but can only drop a harmless cross into the arms of David Ospina.
64'
Goal
Marko Arnautovic. Assist by Manuel Lanzini (West Ham United)
64'
GOAL!!! WEST HAM
It's been coming! Cheikhou Kouyate's blocked shot bounces back to the midfielder, and he quickly passes to Manuel Lanzini on his left. The Argentine slips a great pass to MARKO ARNAUTOVIC on the left of the box, and the talented forward takes a touch before lashing a pinpoint angled drive into the far bottom corner of the net.
7'
WARDROBE MALFUNCTION
There's an odd stoppage as the ref trots over to the touchline and appears to have his sleeves rolled up by the fourth official. The players look completely nonplussed by the interruption.
63'
OVER FROM ARNAUTOVIC
As the ball bounces around the Arsenal box following a corner, Hernandez leaps to nod it down to Arnautovic, who volleys over from close range.
62'
Yellow Card
Ainsley Maitland-Niles (Arsenal)
62'
YELLOW CARD
Ainsley Maitland-Niles is cautioned for booting Mark Noble on the foot as the latter makes a clearance.
61'
SUB FOCUS
The two substitutes combine to very nearly make an instant impact; Lanzini sends a free kick curling all the way to the far post, where Hernandez steals around the back and directs an awkward header over the crossbar.
60'
Substitution
Chicharito Hernandez (on). Joao Mario (off). (West Ham United)
60'
DOUBLE SUBSTITUTION
David Moyes decides a shake-up is required, replacing Edimilson Fernandes and Joao Mario with Manuel Lanzini and Javier Hernandez. The little Mexican will partner Marko Arnautovic up front.
60'
Substitution
Manuel Lanzini (on). Edimilson Fernandes (off). (West Ham United)
57'
GUNNERS FIRING
Aaron Ramsey passes out to Iwobi on the right and shouts for the return ball, steering a venomous shot just wide from the edge of the penalty area. Arsenal look rampant now.
55'
TOO MANY TOUCHES
Lacazette takes too many touches as he tries to weave his way through a wall of bodies inside the box, eventually lining up a shot that Declan Rice is able to block at a stretch.
53'
CROSS PURPOSES
Alex Iwobi makes a barnstorming run into the box on the right, leaving Masuaku for dead, but the youngster's chipped cross is nowhere near finding a colleague.
51'
Goal
Nacho Monreal. Assist by Granit Xhaka (Arsenal)
51'
GOAL!!! ARSENAL
Granit Xhaka flights a corner to the penalty spot, where NACHO MONREAL is somehow left completely unmarked to connect with a powerful volley. Arthur Masuaku looks well placed to block the effort at the near post but inexplicably moves out of the way, allowing the ball to hit the back of the net.
50'
Yellow Card
Pablo Zabaleta (West Ham United)
50'
YELLOW CARD
Pablo Zabaleta has clearly lost a yard of pace because the veteran defender is nowhere near reaching Welbeck out on the wing in time to make a clean tackle. Welbeck is sent flying and the ref issues a yellow card.
48'
STRAIGHT AT THE KEEPER
Alexandre Lacazette turns back on himself to create space for a dinked ball into the centre which Danny Welbeck knocks down with his chest. Nacho Monreal is on hand to thrash the bouncing ball towards goal from near the penalty spot, but the full back's effort is straight at Joe Hart.
46'
SECOND HALF
The teams are back out and the second half is underway, with neither manager having made any changes at the break.
West Ham looked highly threatening in the first part of the half, only for Arsenal to bite back strongly and squander a number of decent chances. The Hammers could easily have taken the lead when Joao Mario burst through and shot straight at David Ospina in the 13th minute, and soon after that Cheikhou Kouyate sent a looping header onto the crossbar, Marko Arnautovic then forcing a decent save from Ospina. Arsenal gathered their wits and began to create chances; Laurent Koscielny headed just wide from a corner, while Danny Welbeck almost found the bottom corner from the edge of the penalty area and then almost scored with a header himself. It's still anybody's game; stay tuned for all the action after the break.
45'
HALF TIME ARSENAL 0 WEST HAM UNITED 0
Xhaka sends Ramsey into the box with a clever reverse pass, and the Welshman cracks an effort not far wide of the right-hand post. The whistle then blows, meaning we've reached the break here at the Emirates, where there've been plenty of chances but no goals as yet.
45'
DODGY REF
Angelo Ogbonna gets across the defenders and hooks Mario's corner wide, but the ref strangely gives another corner.
45'
SUBSTITUTION
Elneny is stretchered off covering his face with his shirt; a sad sight indeed. Youngster Ainsley Maitland-Niles is sent on to patrol midfield in his place.
44'
ELNENY HURT
Elneny is accidentally kicked on the foot by Noble as the pair go for a high ball, and it's clear that the midfielder is suddenly in some pain. A stretcher has to be brought on and his leg strapped up; that will be a worry for Egypt's World Cup prospects.
41'
Yellow Card
Granit Xhaka (Arsenal)
41'
YELLOW CARD
Xhaka is awarded an early yellow card for a typically poor tackle, sliding in very late on Arthur Masuaku and sending the West Ham man flying.
90'
ARSENAL SAVE BEST FOR LAST
Arsenal scored three goals in the last ten minutes to beat West Ham 4-1 at the Emirates. The game seemed finely balanced until a terrible mix-up for the Hammers in the 82nd minute, Declan Rice inexplicably ducking an Aaron Ramsey cross, which bounced past a shocked Joe Hart and into the far corner. The floodgates were open, and just three minutes later Alexandre Lacazette scored with a deflected drive from an angle, before grabbing his second with a neat sidestep and close-range finish. The visitors had started the game the stronger side but fell behind shortly after half time when Nacho Monreal volleyed home from a corner. They soon equalised through a superb touch and finish from Marko Arnautovic, at which point the game seemed anybody's, but the final minutes put paid to the Hammers' hopes.
90'
FULL TIME ARSENAL 4 WEST HAM UNITED 1
The final whistle confirms a thumping 4-1 win for Arsenal over West Ham, who may still need a few more points to be sure of staying up.
90'
HART IN THE WAY
Bellerin nudges the ball to Aubameyang, who enters the penalty area from the right and goes for goal, only to find Hart equal to it.
90'
OVER FROM XHAKA
Xhaka passes forward to Lacazette, who battles for the ball with his back to goal before returning the favour. Xhaka leans back to place a shot over the bar when he really should have scored.
38'
WELBECK AT A STRETCH
Lacazette sprints upfield on the break and sweeps a ball to the back post, where Welbeck stretches to head it down but is unable to link up with a teammate.
35'
WELBECK TOILS ON
Danny Welbeck has to put one of these away soon. Iwobi plays in the overlapping Bellerin, who produces a wonderful cross to the back post, where Welbeck arrives at speed to head over the bar.
34'
STRAIGHT AT THE KEEPER
Declan Rice wipes out Welbeck as the forward squeezes a ball to Lacazette, gifting Arsenal a free kick just outside the area. Granit Xhaka bends the set-piece over the wall but too close to Joe Hart, who beats the fierce strike away without too much trouble.
31'
WELBECK FULL OF BEANS
Danny Welbeck plays a crisp one-two with Mohamed Elneny and heads for the edge of the penalty area but can only drag his finish well wide. The England forward is looking full of energy but short on sharpness.
27'
RAMSEY TAKES A KNOCK
Ramsey goes down in a heap after challenging for the ball with Kouyate, putting extra lines on the face of Arsene Wenger as he sees the midfielder receiving treatment, but his worries are unjustified as 'Rambo' soon gets up to rejoin the fray.
25'
WELBECK THE WANDERER
Welbeck receives a pass infield from Nacho Monreal and wanders along the edge of the box before aiming for the bottom corner with a tasty low strike that skids only just wide of the target.
23'
WOEFUL MISS
Alex Iwobi's clever touch sends Welbeck into the box but wide of the goal, and the former Manchester United man pulls the ball back to Hector Bellerin, who dismays the fans with a poor sidefooter that sails over the bar from just 14 yards out.
21'
WIDE FROM FERNANDES
Fernandes decides to try his luck with an ambitious effort 25 yards from goal on the right, and unsurprisingly the effort drifts comfortably wide.
20'
NOBLE SAVES THE DAY
Lacazette is played into the area and looks like he'll get the chance to shoot, only for Mark Noble to appear from nowhere and nick the ball away from the France forward.
19'
WALKING IT IN
Arsenal reassert themselves with a wonderfully intricate move that sees them work their way into the West Ham box, but they end up doing too much and eventually go backwards into their own half.
16'
OFF THE BAR
Kouyate gets the jump on the defence to meet Mario's corner with a flicked header that loops onto the top of the crossbar and behind.
15'
ARNAUTOVIC DENIED
West Ham continue to make inroads with long balls; this time Arnatutovic gets free in the left channel and produces a powerful drive from an angle that Ospina has to dive and parry away at full stretch.
13'
ARSENAL UNDER THE HAMMER
Mario collects Fernandes' flick-on from a Joe Hart punt and nutmegs Shkodran Mustafi before shooting straight at David Ospina. Moments later Marko Arnautovic bursts into the penalty area and is denied by Mustafi's excellent sliding block as the visitors apply some pressure.
11'
HAMMERS THREATEN
West Ham finally show some threatening play with a lovely passing move that culminates in Joao Mario slipping a deft ball in behind the defence that just evades Edimilson Fernandes. The midfielder would have been clean through on goal.
4'
GUNNERS START STRONG
Arsenal are dominating the early proceedings, with Aaron Ramsey looking dangerous with a couple of forays forward.
1'
KICK OFF
Alexandre Lacazette kicks off a special match at the Emirates, with the fans singing loudly in praise of Arsene Wenger.
0'
WEST HAM TEAM NEWS
The recovery of Angelo Ogbonna from tendinitis means David Moyes is able to field an unchanged team. James Collins and Pedro Obiang remain on the treatment table.
0'
ARSENAL TEAM NEWS
Arsene Wenger has made some changes to the side that lost to Newcastle last weekend, seemingly trying out his likely starting line-up for the Europa League semi-final. David Ospina replaces Petr Cech in goal, while at the back Rob Holding and Calum Chambers make way for Hector Bellerin and Laurent Koscielny. In midfield Chris Willock is replaced by Aaron Ramsey, who has just recovered from a shin problem, and up front it's Danny Welbeck in for Pierre-Emerick Aubameyang. Jack Wilshere is sidelined by an ankle injury.
0'
ARSENAL V WEST HAM UNITED
West Ham still aren't quite clear of danger, but somehow today's game will be all about Arsene Wenger. Now the longest-serving manager in Premier League history has finally announced his departure at the end of the season, even those fans who have long been calling for his head are suddenly talking about the Frenchman as a club legend once again. Wenger has said he will be using this game to prepare for Thursday's Europa League semi-final, so we could see some surprising team selections. The Hammers are six points above the drop zone now but won't be happy until the magical 40-point mark is reached. Today's match represents an excellent opportunity to work towards that against a team who have nothing to fight for in the league. Join me, Luke Ostler, at 1.30pm BST for all the action from the Emirates.