Arsenal 4 West Brom 1

Theo Walcott staked his claim for an FA Cup final place with a first-half hat-trick as Arsenal rounded off their league campaign in style.

The England international, who started for the first time since mid-March – playing as a central striker – repaid Arsene Wenger’s faith in him by netting three goals within 37 minutes.

Walcott’s first league hat-trick since December 2012 was supplemented by a stunning volley from Jack Wilshere as the Gunners rubber-stamped third place in the Premier League, while Gareth McCauley headed in a second-half consolation for the visitors.

The Gunners were a goal to the good inside five minutes as Santi Cazorla picked out a darting run from Walcott, who unleashed a right-foot rocket past Bo Myhill into the roof of the net.

Alexis Sanchez had a couple of opportunities to increase the home side’s lead, walloping a free-kick just over the bar and then sending a low effort trickling into Myhill’s hands.

But Arsenal doubled their advantage on 14 minutes when Wilshere broke to find Mesut Ozil and, although the German could not quite dig out the shot, the ball fell for Walcott to toe-poke home.

Three minutes later, the Baggies half-cleared a corner and Gabriel laid the ball off to Wilshere, who inscribed his name on the scoresheet with a gem of a left-foot volley that zipped into the top corner.

Myhill made Walcott wait a little longer for his treble with a diving save soon afterwards, while Craig Dawson charged down a Sanchez drive as the Gunners continued to rip West Brom to shreds.

But the fourth goal duly arrived eight minutes before the interval when Wilshere burst through and released Cazorla, whose cross bobbled to the far post for Walcott to tap in.

The gap might have widened even further, with Walcott and Wilshere both going close before half-time, and there were ironic cheers when David Ospina was finally asked to get his hands dirty, fielding a deflected James Morrison free-kick.

There was no respite after the break for Myhill, who sprang to his left to push away Cazorla’s curling effort, with Walcott sliding in but unable to convert the rebound.

However, the Baggies pulled a goal back on 57 minutes as substitute Victor Anichebe won a corner and Ospina was left floundering by Chris Brunt’s centre as McAuley rose to head past him.

Inevitably, the game began to drift and Wenger rang the changes, with Alex Oxlade-Chamberlain making his return from injury as one of three substitutions.

Another of the replacements, Aaron Ramsey, was unlucky not to score late on – crashing a drive against the post and then aiming a measured chip towards the corner, only for Myhill to claw it onto the woodwork.

At the other end, Brunt and Chris Baird went close and Craig Gardner was unfortunate not to score a second for the visitors in added time as his shot squirmed from Ospina’s grasp but grazed the bar.

Arsenal: Ospina; Bellerin, Mertesacker, Gibbs; Coquelin (Ramsey 69), Cazorla; Wilshere (Oxlade-Chamberlain 76), Ozil, Sanchez; Walcott (Giroud 69).