The efficient Arsenal front line made more of the high back lines | David Pleat

Both sides squeezed the centre of the pitch, leaving space behind, but the Arsenal strikers took better advantage of it

This was a helter-skelter occasion, a game of huge excitement with all caution thrown to the wind, and at its conclusion the professor had gazumped the apprentice. Yet the thrill this match provided was encouraged throughout by naive defending from both sides. On the day, the efficiency of Arsenal’s forwards better masked their own team’s defensive vulnerability. Chelsea missed their opportunities and paid the price.

It was the eagerness of both sides to play such high defensive lines that opened this contest up. Arsenal set that tone early on, with Per Mertesacker squeezing the play to keep Fernando Torres further away from goal and, in doing so, ensure the distances between the visitors’ backline, midfield and frontline stayed relatively short. The upside of the tactic was that the visitors were never strung out and, when possession was regained, they were close to each other to support. The flip side, though, was the pockets of space left between defenders and the acres behind them that Chelsea’s forwards sought to exploit.

A sharper home attack would have punished the Arsenal bravery. They ran invitingly and unopposed behind Arsenal’s full-backs in the contest’s opening minutes and might have established a healthy early lead. It was a dangerous tactic for Arsenal to adopt, given that top-quality players, given a fraction of a second, can time a pass to perfection and send team-mates bearing down on goal. Mertesacker might have preferred to have sat deeper among his back four. Yet he was spared at times here because Daniel Sturridge seemed uncertain of touch, Torres was passive and Juan Mata was unable to command the ball enough to dictate the proceedings.

But Chelsea too, perhaps somewhat surprisingly, played high and left space behind, which Theo Walcott, in particular, relished. The England winger ran merrily beyond Ashley Cole (see diagram), his accurate selection of pass a pleasing improvement. The opportunities passed up by Gervinho and Robin van Persie in the opening 15 minutes were an indication of how open Chelsea were, with Walcott outpacing Cole at will. When playing such a high line, there must always be pressure exerted on the player in possession who is seeking to thread the ball through. It said a lot for Aaron Ramsey’s performance that, after the interval in particular, he was able to escape the attentions of Mikel John Obi when Arsène Wenger pushed the Welshman further forward to contribute telling passes.

With Alex Song holding, Ramsey was better able to express himself; his is an old head on young shoulders, twisting and turning, with his timing of the pass spot on. Given responsibility, and now injury-free, Ramsey could prove inspirational. Gervinho was bright and worked hard, offering Van

Robin van Persie is on fire for Arsenal, says Arsène Wenger

• Wenger praises prolific Dutchman Robin van Persie
• Manager also lauds Aaron Ramsey and Laurent Koscielny

Two months ago Arsenal felt the trauma of being on the receiving end of a catastrophic result. They have come a considerable way since they were defeated 8-2 by Manchester United, and in this most capricious of seasons, they experienced the other side of the coin after a 5-3 spectacle won at Chelsea’s expense at Stamford Bridge.

On a day to forget for John Terry, whose blunder helped Arsenal on their way, Robin van Persie again proved instrumental in maintaining his team’s renewed zest for winning football. Arsène Wenger praised his talisman, who took his incredible goalscoring statistics to 28 goals from 27 Premier League games in 2011 with a beautifully polished hat-trick.

“He is, of course, on fire,” the Frenchman said. “He takes advantage with class of the fact we attack a lot, that we create chances. The intelligence of his movement around the box and the accuracy of his finishing is exceptional.”

His was not the only expert performance on the day. Wenger also had praise for the “outstanding” Laurent Koscielny, who marshalled Arsenal’s resistance with impressive composure, and Aaron Ramsey in midfield, whose imaginative prompting ensured his team created numerous chances. Another who deserves to feel proud of himself is Theo Walcott, who delivered his most rounded performance of the season and crowned it with an audacious strike.

The difference between this performance and the anxious and inhibited displays at the start of the season is stark. “What has changed is we got half of the team in on 31 August,” Wenger said. “We had to rebuild complete unity in the way we want to play football. Every win makes you stronger. Now the players get used to the way we want to play so we get stronger. We have still some ground to make up in the league, and the teams in front of us do not drop many points. The quality we have shown today should make us more confident.

“We showed great spirit because when you are 2-1 down just before half time… we came out straight away with a complete desire to go forward. We looked dangerous for the whole game and I hope the team continues to focus on getting stronger and stronger.”

From a position of peering above the relegation zone, Arsenal are now within three points of a Chelsea team whose status in the top-four establishment has never been questioned. André Villas-Boas was at pains to write this off as a freakish result. “Regarding the 5-3, I have nothing to say because we were three minutes on the clock, trying to get 4-4 and we were completely outbalanced. Arsenal made the most of it.”

He refused to be critical of his creaking back four, adding: “You have to take two goals out of the situation. One is a slip from a player, which is nothing to do with defensive organisation, and the other is when you are trying to do something with three minutes on the clock. We committed mistakes, we will try to improve.”

Even though Chelsea have played an open style in their games against top four rivals, they have lost to both Manchester United and Arsenal. But Villas-Boas has no intention of changing their approach. “Because the philosophy is a personal value and a club value,” he said. “You should never sell it cheap. We will stick to this philosophy.”

Wenger wondered whether the goalfests in the Premier League are more down to attacking quality or defensive vulnerability. Amazingly, in matches between England’s Champions League teams, there is an average of 6.8 goals scored. It brings to mind José Mourinho’s comment after Arsenal beat Tottenham 5-4 at White Hart Lane a few years ago. “It was a hockey score,” he sneered. Nothing wrong with this kind of hockey.

Premier League 2011-12Arsène WengerRobin van PersieArsenalPremier LeagueChelseaAmy Lawrenceguardian.co.uk

In pictures: Chelsea v Arsenal

A selection of pictures from Saturday’s remarkable 8 goal London derby at Stamford Bridge