The Reds get their first win of the season, while injuries and suspensions build up for Arsene Wenger's men as Koscielny limps off and Frimpong sees red.
An unfortunate Aaron Ramsey own goal and a late Luis Suarez stike gave the visitors their first victory of the new season.
Chances were few and far between for both sides in a game that turned into something of a midfield battle. Andy Carroll had Liverpool’s best chance in the first half and Robin van Persie had a great opportunity in the second half before the bizarre own goal.
The deadlock was broken with 11 minutes to play and it was Liverpool’s substitutes who combined but it was an unfortunate deflection that gifted the Reds the lead. Raul Meireles and Suarez linked up inside the area, but as Ignasi Miquel tried to clear the ball it struck Ramsey and looped over Wojciech Szczesny into the back of the net.
Arsenal brought Nicklas Bendtner on for Theo Walcott as the club went in search of an equalizer but the Dane struggled to get involved in the game and it was the Reds who looked more likely to score as Meireles went close in the closing minutes to doubling their lead.
And substitute Suarez did double the lead in the final minute with a tap in from seven yards. Lucas found Meireles unmarked on the right of the Arsenal penalty area, he rolled the ball past Szczesny to the Uruguayan who fired the ball into the unguarded net and seal the points for the visitors.
Arsenal manager Arsene Wenger was forced to hand debuts to Carl Jenkinson and Emmanuel Frimpong, but the biggest surprise in the Gunners lineup was the inclusion of Samir Nasri. The Frenchman was recalled to the starting lineup despite being expected to leave the club in the coming days, and as with injuries ravaging the Arsenal squad there was also places on the bench for talented duo Alex Oxlade-Chamberlain and Ryo Miyaichi
Arsenal's injury woes worsened in the 14th minute as Laurent Koscielny broke down with what appeared to be a lower back problem. Much to the dismay of Wenger, the French defender was unable to continue and was replaced by young Spaniard Ignasi Miquel for his Premier League debut.
Frimpong’s debut ended on a sour note with a red card. The midfielder mistimed his challenge on Lucas in the center of the pitch and referee Martin Atkinson had no option but to issue the debutant with his second yellow card and subsequently a red card.
The dismissal of Frimpong saw both sides make changes with Suarez and Meireles replacing Carroll and Dirk Kuyt for Liverpool, while Andrey Arshavin was sacrificed for Henri Lansbury as Wenger looked to bolster the centre of his midfield.
With their man advantage the visitors began to create more chances and in the space of two minutes Szczesny was forced into good saves from Suarez and Downing from close range. The young goalkeeper able to turn away both efforts as the rain poured down in north London.