Three goals in a frightening seven-minute spell condemned Norwich City to defeat at Arsenal, in a game they had led for most of the second half and deserved more than the defeat they left north London with.

After a nervy first half, Michael Turner's header had given City a 57th minute lead, but the game hinged on a controversial 85th minute penalty decision that ultimately got the top four-seeking Gunners up and running at The Emirates.

With Wes Hoolahan not in the squad, Chris Hughton made three changes from the 2-2 draw with Swansea – Steven Whittaker, Grant Holt and Alex Tettey coming into the starting XI, with Javier Garrido and Elliott Bennett dropping to the bench.

But there was no sign of Anthony Pilkington, who was confirmed as fit and available following his hamstring injury by Hughton on Thursday.

Meanwhile, Arsenal welcomed back Jack Wilshere and ex-Norwich loanee Kieran Gibbs with captain Thomas Vermaelen replacing the suspended Per Mertesacker. Theo Walcott returned to the bench following injury.

Arsenal started looking like they meant business as they pressed and pushed their struggling visitors. But they still had to wait for their clear-cut chances.

The first arrived on 24 minutes, as Bacary Sagna was given an age to deliver his cross from the right and Olivier Giroud's flicked header duly flicked the top of Mark Bunn's crossbar.

Gervinho was next, played in by a delicious Santi Cazorla pass but his touch took him wide and the winger could only roll the ball agonisingly across Bunn's open goal.

Arsenal were expected to kick on after the break, but it was Norwich who carried the greater initial potency.

A needless corner given away by Laurent Kosciely saw Michael Turner unable to force an effort on Lukasz Fabianski's goal.

Soon after, Jack Wilshere was appealing for a penalty after an almighty scramble saw his shot blocked by Turner – he claimed handball, replays suggested shoulder.

Then came City's big moment. Kei Kamara was felled by Gibbs down the City right, although how much contact there was could be debated. Still, the familiar sight of Robert Snodgrass delivering a superb left-footed cross from the right led to Michael Turner producing a superb header to give City a 57th minute lead; the centre-back's excellent movement key to his goal and losing Koscielny.

On came Theo Walcott for the tiring Wilshere and his pace immediately had City on the back foot, with Whittaker's clumsy challenge in the box appearing to be a lucky escape.

And City made a change of their own after Bradley Johnson's knock from Sagna's tackle laced with retribution for this time last season got the better of him.

Norwich earned a wonderful chance to make it two as Sebastien Bassong broke from the back into the home half and played in Russell Martin on the overlap, but his crisp strike from 15 yards was straight at Fabianski.

The Gunners then hit the bar for a second time, Bunn doing brilliantly to tip substitute Lukas Podolski's first-time drive on to the face of his crossbar after an incisive move.

But then the game changed on its head in seven devastating minutes.

First was the controversy, as Kei Kamara was penalised for a tug on Giroud's shirt as he cleared a cross. Linesman Richard West gave the spot-kick, Bunn was booked for his protests. Mikel Arteta dispatched the 85th minute penalty, just beyond the keeper's dive.

Three minutes later the hosts had the lead, Alex Oxlade-Chamberlain cutting his way through via a one-two with Podolski before his cross was bundled home by Giroud.

Jonny Howson responded with a great chance that was superbly saved by Fabianski's feet, but with Arsenal now at their frightening best, Podolski finished the job.

Walcott was offside from Giroud's header but allowed to carry on and he squared for the German to rifle beyond an exposed Bunn two minutes into the added six to leave City on the wrong end of a harsh and devastating turnaround.

• Arsenal: Fabianksi; Sagna (Oxlade-Chamberlain, 80), Koscielny, Vermaelen, Gibbs; Ramsey, Arteta; Gervinho (Podolski, 60), Wilshere (Walcott, 60), Cazorla; Giroud. Unused subs: Mannone, Coquelin, Jenkinson, Monreal. Booking: Sagna.

• Norwich City: Bunn; Martin, Turner, Bassong, Whittaker; Howson, Tettey (Jackson, 90), Johnson (Fox, 62); Kamara, Snodgrass; Holt (c). Unused subs: Camp, Garrido, R Bennett, E Bennett, Becchio. Bookings: Bunn, Snodgrass.

• Goals: Arsenal: Arteta (pen, 85), Giroud (88), Podolski (90). Norwich: Turner (57)

• Referee: Mike Jones

• Attendance: 60,095

• Bookings: Arsenal: Sagna (34). Norwich: Bunn (83), Snodgrass (90)