(BBC )Arsenal maintained their 100% start to this season's Champions League with a win against 10-man Partizan Belgrade.
Andrey Arshavin fired Arsenal ahead before Cleo levelled for Partizan with a penalty after Denilson's handball.
Arshavin missed a penalty for Arsenal after Marko Jovanovic was sent off for a foul on Marouane Chamakh before Chamakh scored with a headed.
Sebastien Squillaci's header from a corner extended the lead before Lukasz Fabianski saved Cleo's late penalty.
It was a moment of redemption for the Arsenal goalkeeper, who made a series of high-profile errors in last season's Champions League campaign but was a far more assured presence as replacement for the injured Manuel Almunia.
While this was a far less composed overall display from the Gunners than the one they produced to blow away Braga 6-0 in their opening Group H fixture, it contained enough quality to make the win a deserved one and go some way to eradicating the memory of Saturday's 3-2 home league defeat by West Brom.
A faulty floodlight meant the game began with one corner of the Stadion FK Partizan in darkness, but the home side began brightly against a nervous Arsenal backline.
Brazilian striker Cleo was muscled out after initially breaking clear but from the breakdown Nemanja Tomic would surely have scored but for a superb last-ditch tackle from Denilson.
Arsenal though have the ability to unlock even the toughest of European defences and they took the lead with a typically incisive move, albeit from their first real attack of the game. Alex Song found Arshavin, who continued his run after moving the ball on to Jack Wilshere, collecting a superb drag back from the young England player before drive low past home keeper Vladimir Stojkovic.
The goal was the perfect tonic for the Gunners, who proceeded to boss possession and regularly threaten the home defence with some superb attacking football for the next 20 minutes.
Arshavin was central to the Gunners' play as firstly he was found again by Wilshere in the box only to see his shot smothered by Stojkovic and then minutes later beat the keeper with a superb, delicate chip only to see the effort acrobatically cleared off the line by the back-tracking Jovanovic.
If Partizan were to get a foothold back in the game it would need a moment of brilliance or an Arsenal error. The visitors duly obliged with the latter when an innocuous cross from Radosav Petrovic was unnecessarily handled by Denilson in the box, Cleo calmly sending Fabianski the wrong way from the penalty spot.
Arsenal were given a superb chance to take control of the game again early in the second half when Jovanovic brought down Chamakh in the box to concede a penalty and, as last man, earn himself a straight red card.
But Arshavin's penalty was struck straight down the middle and saved by the legs of Stojkovic.
However, it did not take long for Arsenal to make use of their numerical advantage as Rosicky's cross found Chamakh and, despite his first header being superbly tipped on to the bar by Stojkovic, the goal was left exposed for the Moroccan striker to easily nod in.
Squillaci's angled header from a Samir Nasri corner appeared to have ended Partizan's hopes of picking up a positive result until Kieran Gibbs bundled over Ivan Stevanovic for the third penalty of the night.
Cue Fabianski, who superbly palmed away Cleo's spot-kick one-handed.