Arsenal's season went from bad to worse with defeat at West Brom leaving their hopes of a top four finish looking bleaker than ever.

Goals from Craig Dawson - an almost identical brace - and another from substitute Hal Robson-Kanu saw the Gunners slip to defeat and further detached from the race for the Champions League.

Here's what we learned:

West Brom vs Arsenal player ratings Show all 23 1 /23 West Brom vs Arsenal player ratings West Brom vs Arsenal player ratings <b>West Brom:</b> Boaz Myhill – 7 out of 10 Left stranded for Giroud’s header as he was given no chance from close range. Otherwise commanded his area very well, and his good day’s work was summed up with a late save from Koscielny’s volley. 2015 Getty Images West Brom vs Arsenal player ratings Craig Dawson – 7 out of 10 Had his work cut out in the second half as Sanchez switched to the left. But he did well to reduce the threat from Gibbs and frustrated the Chilean forward late on. 2015 Getty Images West Brom vs Arsenal player ratings Jonny Evans – 7 out of 10 Showed his valuable experience as he stuck to Giroud in open play, giving the Frenchman no chance of getting a clear-cut effort on goal. West Brom vs Arsenal player ratings Jonas Olsson – 5 out of 10 At fault for Giroud’s opener as he lost his man at Özil’s free-kick. Guilty of messing around with the ball ahead of Arsenal’s penalty, though that may have had its desired effect on Cazorla. 2015 Getty Images West Brom vs Arsenal player ratings Chris Brunt – 7 out of 10 Perfect delivery gave Morrison the chance to score from his free-kick. Tried to get forward when possible, but today he knew his duty came in defence and he forced Bellerin to try and go outside him each time he attacked. 2015 Getty Images West Brom vs Arsenal player ratings James Morrison – 8 out of 10 Expertly finished with the outside of his right foot to volley home and level the scores from a Brunt free-kick. Worked his socks off to try and disrupt the Arsenal midfield axis, with a fair amount of success. 2015 Getty Images West Brom vs Arsenal player ratings Darren Fletcher – 6 out of 10 Sat quite deep to partner Yacob in shielding the back-four, although he didn’t have many stand-out moments. 2015 Getty Images West Brom vs Arsenal player ratings Claudio Yacob – 6 out of 10 Another who was fairly anonymous when it came to game-changing decisions, but he was always in position to cut out a killer ball and Tony Pulis could ask no more of him. 2015 Getty Images West Brom vs Arsenal player ratings James McClean – 8 out of 10 Fantastic run down the left before crossing into goal-mouth produced Arteta’s own-goal. He gave Bellerin plenty to think about as he drifted across the midfield at will. 2015 Getty Images West Brom vs Arsenal player ratings Stephane Sessegnon – 6 out of 10 Played in McClean for the second after committing Koscielny to pull Arsenal’s defence ragged. 2015 Getty Images West Brom vs Arsenal player ratings Solomon Rondon – 5 out of 10 Fairly anonymous and was hauled off for Saido Berahino in the second half. The England Under-21 striker looked much more of a threat. 2015 Getty Images West Brom vs Arsenal player ratings <b>Arsenal:</b> Petr Cech – 6 out of 10 Slightly off his line which allowed Morrison to volley the ball over his head, but there was little he could do for the second goal. Reaction save stopped a late Berahino effort although the whistle had already gone. 2015 Getty Images West Brom vs Arsenal player ratings Hector Bellerin – 6 out of 10 Lost Morrison for the goal as he was caught napping when the ball was airborne. Looked short on match fitness, although he was his ever keen self to work down the right in search of the equaliser. 2015 Getty Images West Brom vs Arsenal player ratings Laurent Koscielny – 5 out of 10 Still not his normal self and Wenger was right to question whether he should play him in the build-up to the match. Simple header back to Cech went for a corner, and he lost Berahino late on. 2015 The Arsenal Football Club Plc West Brom vs Arsenal player ratings Per Mertesacker – 5 out of 10 Went AWOL for the second goal which forced Arteta back into defence. Looked nervy on the ball, and still struggles to connect with attacking aerial balls. 2015 The Arsenal Football Club Plc West Brom vs Arsenal player ratings Nacho Monreal – 6 out of 10 The Spaniard didn’t press forward as much as he has recently with Gibbs in front of him sticking to the left, and that had an impact on Arsenal’s attacking threat as there were few overlaps from the left-back. Fairly solid in defence though, with little threat coming down his flank. 2015 The Arsenal Football Club Plc West Brom vs Arsenal player ratings Francis Coquelin – 5 out of 10 Lasted just 13 minutes after his own sliding tackle saw him suffer a knock to his knee. Replaced by Mikel Arteta, with disastrous consequences. 2015 Getty Images West Brom vs Arsenal player ratings Santi Cazorla – 4 out of 10 His form has deserted him recently. His passing was terrible in attacking positions, and his dreadful penalty attempt sums up Arsenal’s day. Slipped as he kicked the ball, sending it into his standing foot and over the bar. 2015 Getty Images West Brom vs Arsenal player ratings Alexis Sanchez – out of 10 Worked extremely hard but couldn’t fashion many chances for himself. One clear effort saw the ball escape his reach with the goal at his mercy. 2015 The Arsenal Football Club Plc West Brom vs Arsenal player ratings Mesut Ozil – 7 out of 10 Broke the record for consecutive assists as his floated free-kick saw Giroud head home to register a seventh straight game in which he’s set up a goal. Probed throughout and looked to be Arsenal’s creator for the equaliser – only it never came. 2015 Getty Images West Brom vs Arsenal player ratings Kieran Gibbs – 5 out of 10 Dangerous cross late in the first half went unpunished as no one in red could reach it. Not an out-and-out attacking player though and it showed, and he was replaced by Joel Campbell with half an hour to go. West Brom vs Arsenal player ratings Olivier Giroud – 6 out of 10 Emotion poured out of him before kick-off as La Marseillaise rang out, and he soon had something to shout about as he headed in Ozil’s free-kick. Booked late in the first half as Arsenal lost their way, and he faded in the second half. 2015 Getty Images West Brom vs Arsenal player ratings Mikel Arteta – 1 out of 10 Terrible introduction for injured Coquelin after 13 minutes in. Conceded the free-kick that led to Morrison’s goal – though he appeared to get a toe on the ball – before handling in an own-goal to give Baggies the lead. His nightmare outing was capped when he was injured three minutes after the break, and was replaced by Mathieu Flamini having played 36 minutes. 2015 Getty Images

Arsenal fans divided

Wenger in or Wenger out, that is the question. If you needed any more evidence of how split Arsenal have become as a club here it was at the Hawthorns. First, a plane flew over the ground at kick-off with a banner emblazoned with the words “No new contract #WengerOut” on it. Then came a second plane, halfway through the first-half, with an “In Arsene We Trust #Respect” message. If Gunners fans can’t decide what they want, how are the board supposed to? Arsenal are a club divided off the pitch and it isn’t what they need on the pitch either.

Defence the best form of attack for West Brom

West Brom might not have a guaranteed 20-goal-per-season striker – but who needs one when your centre-backs score for fun in its place? Craig Dawson got the Baggies on the board with a header from a 12th minute corner – the 13th time they have done so from such a scenario this term - and went on to add a second to compound the Gunners' misery. They were the 26-year-old’s first and second of the year but was the tenth from a central defender this season. Jonny Evans also has one while Gareth McAuley has an incredible six, all at 37 years young.

Craig Dawson celebrates scoring against Arsenal (Getty)

Sanchez’s rough treatment

Antonio Conte wasn’t at all pleased with Manchester United’s treatment of Eden Hazard on Monday evening and you can expect a similar response from Arsene Wenger after Alexis Sanchez was targeted with some very rough treatment from the home side. Tony Pulis understandably had no intention of giving the Chilean the freedom of the West Midlands this afternoon. But there’s playing hard and there’s crossing the line. A particularly meaty James McClean challenge in the first half fell firmly into the latter category and was representative of a very physical gameplan designed to counteract the Gunners’ star man.

Alexis Sanchez had a tough afternoon (Getty)

Walcott’s bad week

It’s not been the best few days for Theo Walcott. First he was snubbed by Gareth Southgate for a place in the England squad (on his birthday no less). Then today he completed 65 almost completely ineffectual minutes before being hooked in favour of Olivier Giroud as Arsenal chased an equaliser. Walcott has enjoyed one of his best seasons in recent memory but is in danger of seeing it petering out, much like his team, with more performances like this one.

Robson-Kanu the ultimate super-sub