5 things we learned in the Premier League's midweek action: Out-of-sorts Arsenal

With another round of Premier League action in the books, we take a look back at some of what we learned from the latest slate of matches.

Arsenal wasteful, but it's the referee's fault

Fraser Forster was fantastic between the sticks, but Arsenal's inability to breach him and Southampton is extremely worrying for its title credentials. It was the Gunners' third consecutive Premier League match without rippling the net for the first time since February 2009.

Should reports be believed, Arsene Wenger aired his grievances at referee Lee Mason after the final whistle, saying: "It's always the same with you."

Then Saints' gaffer Ronald Koeman apparently leapt to the defence of Mason, telling Wenger: "No, it's always the same with you. You had 10 chances to score and couldn't take any of them, so why have a go at them?"

Koeman next kicked away some kryptonite, crawled onto the ceiling to avoid Victor Wanyama's agent, and told Robin to make him a cup of tea.

A weight on Adebayor's shoulders

Crystal Palace is in free fall.

One of Alan Pardew's players managed to get on the scoresheet in Scott Dann (making it a league-high seventh time one of the team's defence has grabbed a goal) but not one of his strikers has scored from open play in the Premier League this season.

So after what appeared to be a rather leisurely time out from the game, that goalscoring burden now lies firmly on the shoulders of Emmanuel Adebayor - because obviously Fraizer Campbell and Connor Wickham won't offer much help in that department.

Related: Crystal Palace's Adebayor kept fit during time out with pick-up games

The Togolese rattled a late effort narrowly wide following his 58th-minute introduction, meaning his new side fell 2-1 at home to Bournemouth. A few more bad results and the Eagles will be looking nervously over their shoulders at the drop zone.

Ross Barkley bosses from midfield

Yes, both his goals came from the spot, but the way Ross Barkley strode forward with purpose, looking for opportunities to shoot or release an Everton colleague is extremely encouraging for the rest of the campaign.

Roberto Martinez recently urged his midfielder to show more risk in the final third, even if his pass percentage suffers as a result, and from his performance in the 3-0 win over Newcastle United it looks like he has taken on his Spanish boss' advice.

Barkley's adventure on the ball is superb news for a club that should be much higher than 11th, and certainly food for thought for England manager Roy Hodgson.

Sunderland significantly strengthened

Sunderland lost 1-0 to visiting Manchester City on Tuesday, but the Stadium of Light faithful will take a lot of comfort in the performances of newcomers Jan Kirchhoff, Lamine Kone, and Wahbi Khazri.

Khazri looks to have the ability of his new teammate Sebastian Larsson at set-pieces but, unlike the Swede, the Tunisian is adept when the ball's moving, too. Kirchhoff and Kone, meanwhile, were impenetrable for the most part and seemed to lift the performance of right-back Billy Jones as well.

Vardy dazzles against Liverpool

Netting in back-to-back games for the first time since his record-breaking 11-game scoring streak, Jamie Vardy is looking sharp again after mid-season minor surgery to his groin; and nothing displayed that more than his rocket of a hit that looped over the despairing Simon Mignolet from 25 yards.

Leicester City follows the 2-0 trumping of Liverpool with trips to Manchester City and Arsenal. Even two points from those fixtures means the Foxes are a serious title contender, especially given their extremely generous run of fixtures to follow.