Theo Walcott, centre right, celebrates after scoring his third goal

Theo Walcott plundered a hat-trick as Arsenal gave themselves the perfect warm-up for the FA Cup final with a 4-1 win over West Brom in the last match of the Barclays Premier League season.

Walcott, who has yet to commit his long-term future to the Gunners, laid down a marker to be included in the starting XI at Wembley with a blistering first-half display from a central striker's role.

The England forward, who has battled back from a serious knee injury, cracked in the opening goal after just four minutes, and then quickly doubled Arsenal's lead before Jack Wilshere, on his 100th league appearance, volleyed in a superb third.

Walcott completed his hat-trick on 37 minutes with a close-range tap in to end the match as a contest before half-time.

Just before the hour, Gareth McAuley headed a consolation for the Baggies, who had beaten champions Chelsea 3-0 in midweek.

Gunners boss Arsene Wenger and his squad returned to the pitch after the final whistle for a lap of appreciation having secured third place and with it automatic qualification for the Champions League.

It was a blistering start by the Gunners.

Santi Cazorla played the ball into the right side of the West Brom penalty area, where Walcott - making a first start in the Premier League since March 14 - turned back inside before firing a shot back past Boaz Myhill and into the roof of the net.

It was a first goal at home for the Gunners in four matches, and Wenger's side were soon back on the offensive as Walcott doubled the lead on 14 minutes.

The England forward rode a flying tackle from Jonas Olsson before stabbing the ball into the net through a crowded West Brom penalty area.

After taking in the adulation of the Clock End, Walcott made a point to run over to the Arsenal bench and embrace club physio Declan Lynch, who had helped on the long recovery from a serious knee injury which shattered the player's World Cup dream last year.

Arsenal were 3-0 ahead on 17 minutes when Wilshere sent a fierce left-footed volley into the top corner from 22 yards out following a tee-up from Mesut Ozil, before also going to give Lynch a hug, the 23-year-old having spent more than his fair share of time in the treatment room again this season.

Walcott was denied a first-half hat-trick as Myhill produced a flying one-handed save.

The Baggies defence was, though, breached again on 40 minutes as Wilshere weaved into the left side of the penalty area, feeding Cazorla, whose scuffed shot back across the face of goal was tapped in by Walcott at the far post.

Myhill was soon called into action again earlier in the second half, beating away Cazorla's drive.

West Brom brought on both Victor Anichebe, for Olsson, and then Craig Gardner, replacing Callum McManaman, but it was now a case of damage limitation.

McAuley finally gave the massed ranks of Baggies supporters something to cheer when he got up above Arsenal goalkeeper David Ospina to head in a consolation from a corner on 57 minutes.

Gunners midfielder Alex Oxlade-Chamberlain made a cameo appearance for the final 13 minutes, having been out since early March, but now could also be in contention for Wembley.

Substitute Aaron Ramsey struck the post with a fierce 18-yard drive during the closing stages, with a curling effort from the Wales midfielder then touched onto the angle by Myhill.

Ospina enjoyed a slice of luck in stoppage time as a shot from Gardner went through his hands, but spun up onto the top of the crossbar.

PA Media