Giroud left seeing red but Gunners hold on to kill off Hoops
Arsenal survived the sending-off of striker Olivier Giroud for a reckless headbutt to beat QPR 2-1 at the Emirates Stadium and close back up on the top four of the Barclays Premier League.
The Gunners were in cruise control following Alexis Sanchez's 10th league goal on 37 minutes, the Chilean having seen a tame early penalty saved.
However, a rush of blood from France striker Giroud at the start of the second half reduced Arsenal to 10 men. The Frenchman charged into Nedum Onuoha, the defender hitting the ground in front of the referee.
Czech midfielder Tomas Rosicky, making a first start of the season, swept in a second on the break before Charlie Austin set up a tense finale when he converted a penalty with 11 minutes left.
Unlike at Liverpool last weekend, Arsenal held on under late pressure to move within two points of Southampton and one behind fifth-placed West Ham, whom they play tomorrow.
Arsenal manager Arsene Wenger said: "From the moment of the sending off, we knew we were in a battle.
"It was was a deserved red card, Olivier didn't control himself. It completely changed the dynamic of the game, we were completely in control at that stage and it was quite comfortable.
"Olivier is a guy who, when he makes mistakes, he stands up and admits it."
He added: "We find ourselves detached from the teams above us at the moment, with a bit of ground to make up, so we can't get too carried away with trying to make up that ground at the moment, just to concentrate on what we're doing."
Rosicky said: "It was my first start of the season and I wanted to show the boss he can use me more.
"For every player it's difficult when you don't play for a while and then suddenly you get called up, but you have to be prepared to be called in to action at short notice, so I work incredibly hard in training. This is a special time of year for supporters, when the whole world is watching the Premier League. It's tough for us as players, but you have to embrace it."
QPR manager Harry Redknapp said: "Once they went down to 10 men, at 1-0 you've got to make sure you keep it tight.
"The one thing we didn't want to do is conceded another goal. To let the second goal in when we did was criminal."