The Bundesliga champions dominated possession throughout and created a number of decent opportunities which the Gunners were indebted to goalkeeper Petr Cech for cancelling out.
However, an Olivier Giroud header from Santi Cazorla’s free-kick 13 minutes from time put the hosts ahead before Mesut Ozil made sure of victory, beating Manuel Neuer from close range in added time.
Co-commentating on BBC Five Live, Harton admitted he couldn’t quite believe the Gunners pulled it off considering Bayern’s dominance in possession before highlighting their growing momentum.
“I can't believe they've beaten Bayern with all the possession Bayern have had. Goals win games. A massive result tonight. Arsenal needed a result and three points,” he explained.
“They are firmly back in the group and it keeps the momentum going. On Saturday they can go top of the Premier League. They had to defend for their lives but what a win for Arsenal."
Arsenal’s performance and result wasn’t any fluke. They managed to beat Manchester City away 2-0 playing a similar way and most recently Manchester United at the Emirates.
Bayern were always going to dominate possession, but by dropping deep it allowed the Gunners to have plenty of space in-front of them for Alexis Sanchez, Mesut Ozil and Theo Walcott to exploit.
Petr Cech had to be at his very best to deny Robert Lewandowski and Thiago Alcantara, yet Bayern were quite minited in overall clear opportunities and the longer it stayed 0-0, the more it suited Arsenal.
While the challenge ahead still looks daunting, momentum is key and if the North Londoners can maintain their winning run domestically, they will then head to Munich believing they can win.