Own Correspondent|Arsene Wenger believes Chelsea broke ‘rule number one’ during their Champions League defeat to Bayern Munich on Tuesday evening.

Frank Lampard’s side had chances to take the lead in the first half but failed to captalise and Bayern’s dominant second-half display saw them run out 3-0 winners at Stamford Bridge.

A quick-fire double from Serge Gnabry gave Bayern a comfortable advantage before Robert Lewandowski sealed the victory.

Chelsea now face a mountain to climb ahead of their second leg in Germany on March 18.

And Wenger admits Frank Lampard’s side were punished as soon as they lost control in midfield.

‘What has he [Lampard] learned… but he knew already, because you don’t lose five home games if your team is superior to every other team,’ Wenger told beIN Sports.

‘But at that level, to give possession away you’re punished at some stage because they make you run too much, and you cannot survive for 90 minutes.

‘In the Champions League, if you lost the midfield you’re in trouble, it’s rule number one.

Bayern Munich finished with the authority of a side with no interest in ever letting Chelsea off the hook again. The gulf in class was enormous from beginning to end and, while there will be no shortage of nostalgia before the second leg takes place at the Allianz Arena on 18 March, it is unlikely to feel like much more than a sightseeing exercise when Frank Lampard’s erratic side visit the scene of their greatest triumph.

The painful truth is that a 3-0 defeat flattered Chelsea and, barring one of the greatest comebacks in the history of this competition, this tie is surely over. Bayern, seemingly on a mission to erase the memories of their inexplicable defeat to Chelsea in the 2012 final, were just as devastating as they were when they smashed Tottenham 7-2 in October. The Bundesliga pacesetters made the side sitting fourth in the Premier League look second-rate and all but secured their place in the last eight of the Champions League during a brutal second half, sealing an emphatic win with two goals from Serge Gnabry and Robert Lewandowski’s 39th goal of the season.

It was Gnabry who took the game away from Chelsea with an electrifying four-minute burst shortly after half-time; to think Arsenal let him slip from their grasp. Gnabry has scored six in his last two visits to London and his understanding with Lewandowski, who created both of the German’s goals, was far too slick for Chelsea.