Arsenal 0 Aston Villa 2: ARSENE WENGER is rarely rendered speechless but inglorious inconsistency is taking its toll.

The Arsenal manager winced through his post-match duties on Saturday, breaking off from his deflated monotone only to offer Steve Sidwell his sincere congratulations as they passed in the corridor. "There is no rational explanation," he said. "To go from last week's win against Manchester United, and on Tuesday in the Carling Cup, to this . . . there was no energy left in the side. I don't know."

Wenger gives the impression he has seen it all but this campaign is proving enlightening for all the wrong reasons.

Consistency wins teams titles. That is hardly a revelatory concept. The modern Premier League has been won only once by a team that has lost more than six games in a campaign, with Blackburn beaten seven times 14 seasons ago, and there is little to suggest things will be different this time around.

It is hazardous to write off Arsenal given that this is a side capable of the wondrous - witness that stunning victory over United - but no team capable of mustering such baffling highs and lows can be considered a true contender. Already beaten by two promoted teams and Fulham, and utterly out-played here by Aston Villa, this side lacks the depth, guile and ruthless instinct required to be champions.

Wenger will bristle at such an assessment but how else can such a stuttering challenge be considered? Arsenal were laboured and befuddled against a team now hovering at their back. It says everything about the nature of this year's Premier League - outside Chelsea and Liverpool - that the Londoners are saddled with the same infuriating failings as Villa. Arsenal have already lost to Hull and Stoke while Villa conjured their first victory at these opponents in 15 years on the back of mystifying defeats by Newcastle and Middlesbrough.

"I fully expect us to win the league now," said Martin O'Neill, but he was joking. Wenger said with a straight face that his own team are still in the running, though that was arguably just as laughable.

O'Neill would concede his own charges are just as unpredictable. "You'd see a performance like that today and say: 'Why can't they break into the top four?'" he said. "Then again, you might see us scrummaging around for 15 minutes against Boro and think: 'What are you talking about?' It's difficult because the top teams have been there for so long. They recover from disappointment more quickly."

This result was all the more remarkable as the match appeared to be going to script at the interval. Villa had been resilient and incisive on the break but had nothing to show for it.

Ashley Young, tumbling over Theo Walcott's challenge, had earned a penalty the visitors' slicker approach merited only for Manuel Almunia to save the winger's weak effort. Other openings were spurned and at the interval Villa's chance seemed to have gone. Instead the visitors continued to swarm over Arsenal in midfield and were rewarded late on.

Gael Clichy's own-goal from Ashley Young's centre earned the lead and, while Emmanuel Adebayor clipped the post with a header, the superb Gabriel Agbonlahor deserved his goal courtesy of a thumped finish on the break which secured victory.

"We'd have beaten a lot of teams with that performance," added O'Neill. "But people weren't questioning Arsenal after the way they performed against United. They were exquisite then."

Wenger is, at least, consistent in his stubbornness. He has earned that right over his 12-year reign at this club but he has yet to suggest he has the means of eradicating the weaknesses which have undermined his team all season.

There is a lack of canniness in front of his relatively experienced back-line. Denilson and Abou Diaby are both accomplished midfielders operating alongside Cesc Fabregas but there is no ugly enforcer. "You cannot explain Clichy's own-goal by the absence of an experienced player in midfield," said Wenger. Yet it was in the centre where Villa held sway. Arsenal offered no answers.

The manager will pore over the video of this defeat while the majority of his players are absent on international duty this week.

"We were beaten by a team who were sharper than us and that doesn't change however many times you watch the tape," he said. "The first 48 hours after a setback like this are very difficult."

Wenger, haggard and drawn in defeat, will wonder how it ever came to this.

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