Arsenal Manager Arsene Wenger was full of excuses on Saturday evening after the Gunners missed the chance to go top of the Barclays Premier League as his men were soundly beaten 4-0 by a much-improved Southampton at St Mary’s Stadium.

Wenger’s side fuelled talk of a sustained title push with an impressive victory over Manchester City on Monday, but were punished with their BPL heaviest defeat this year in a lethargic display as the hosts ended their run of five league matches without a win in style.

Southampton had picked up just a point from their previous five outings, but, after a slow start, went ahead courtesy of Cuco Martina’s wonderful long-range effort 19 minutes in.

On his maiden league start, Martina became the first Curacaoan to score in the division and Southampton grew in confidence, doubling the lead 10 minutes into the second half via the first of a Shane Long brace.

With limited attacking options on the bench, Wenger saw his side toil in the final third and struggle defensively as they failed to leapfrog leaders Leicester City, who had been beaten 1-0 by Liverpool earlier in the day and were two points clear of Arsenal.

Southampton, missing the injured Graziano Pelle and Cedric Soares, had Jose Fonte head in a third from a corner and Long make it 4-0 in stoppage time shortly after being denied by the woodwork to seal the points on a hugely frustrating evening for the visitors.

An unchanged Arsenal edged the opening stages, but fell behind to the hosts' first effort on target. Per Mertesacker cleared Ryan Bertrand's cross to Martina, who beat Petr Cech with a stunning effort with the outside of his right boot.

James Ward-Prowse dragged a shot wide before the half-hour as the home side grew in confidence, with Steven Davis failing to muster a clean strike on goal after Laurent Koscielny lost possession.

For all their early endeavour, Arsenal's best chances were a tame Theo Walcott shot easily gathered by Maarten Stekelenburg and a header from the Arsenal winger that found the side-netting.

Long almost doubled Southampton's half-time lead, but the striker put his lob over the crossbar.

After the break, Southampton continued to push for another and Sadio Mane's dangerous delivery failed to get the necessary touch early on the second half.

Virgil van Dijk had the ball in the net five minutes after the interval but his header was adjudged offside.

Shortly afterwards Long did make it 2-0 with a breakaway goal. The Republic of Ireland international played a neat one-two with Mane, before turning his team-mate's cross past Cech from close range amid Arsenal complaints over a trip from Long on Koscielny.

Arsenal continued to struggle going forward, with Mesut Ozil and Joel Campbell not influential in the face of incessant Saints pressure.

Alex Oxlade-Chamberlain was introduced for Campbell after the hour, but it was Southampton who remained the more clinical, Fonte heading home from Bertrand’s set-piece 21 minutes from time.

The impressive Long hit a post, but was not to be denied a second when Dusan Tadic set him clear, the Saints forward finishing past Cech to complete a miserable outing for Wenger’s men.

Southampton manager Ronald Koeman said: “You don’t expect a 4-0 win against Arsenal.

“Of course we have a good football team, but we have struggled in recent weeks. But the second half was perfect.

“It was a tough night for Arsenal, we caused them a lot of problems. It was an amazing result.”

Arsenal manager Arsene Wenger said: “I don’t much take too much notice of the scoreline in my consideration but we lost too many challenges; they were sharper than us.

“We were unlucky on the first one [goal]. The first shot on goal from the right-back [Martina] goes in the top corner.

“The second one was a foul on [Laurent] Koscielny and that was the turning point but the referee didn’t see it, then we were exposed on counter-attacks.

“It’s a disappointing result but I have to say well done to Southampton.

“In many challenges we were second best. The referee let a lot go as well but when you’re not dominant that’s the price you pay.”

•Adapted from premierleague.com. Photo shows Arsenal players leaving the pitch after a loss.

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