London - Arsenal booked their place in the last 16 of the Champions League on Wednesday, beating Partizan Belgrade 3-1 in an ultimately comfortable victory at the Emirates.
Substitute Theo Walcott and in-form Frenchman Samir Nasri scored the decisive goals for the Gunners after Partizan's Brazilian-born striker Cleo had cancelled out Robin Van Persie's first-half penalty.
Defeats to Shakhtar Donetsk and Braga in their previous two matches however meant the English Premier League leaders had to settle for the runners-up spot in Group H. Shakhtar finished first after beating Braga in Ukraine.
Arsenal had dominated from the outset, monopolising possession but struggling to find a way through Partizan's densely populated midfield.
Nasri always looked Arsenal's most threatening attacking outlet, and the midfielder created the first half-chance when he found Marouane Chamakh with a cross that the Moroccan striker headed harmlessly over the bar.
Nasri was in the thick of it again on 19 minutes when he lost his marker superbly before threading a low cross through to Van Persie, who could only guide his shot wide of the near post.
At the other end Arsenal remained largely unruffled although they were forced into a defensive reshuffle on 24 minutes when Emmanuel Eboue came on to replace Kieran Gibbs after the fullback turned an ankle.
Arsenal broke the deadlock on the half hour mark via a dubious penalty, Marko Jovanovic harshly adjuged to have bundled over Van Persie by Italian referee Paolo Tagliavento.
Television replays appeared to suggest little contact by the defender on the Dutch striker.
Partizan's players protested to no avail and Van Persie stepped up to blast his spot kick beyond Vladimir Stojkovic.
Arsenal might have had a second near half-time when a defensive slip from Mladen Krstajic let in Van Persie but the Arsenal striker was unable to find the killer pass for Chamakh, allowing Partizan to snuff out the danger.
Despite cruising through the first half however, Arsenal were made to pay for a slack opening to the second period and Partizan got back on level terms when Cleo's speculative shot took a big deflection off Sebastien Squillaci and looped up over Lukasz Fabianski.
It looked like the match might finish in a draw until the introduction of substitute Walcott for Andrei Arshavin breathed new life into the Arsenal attack with 23 minutes to go.
On 73 minutes Walcott fired Arsenal back into the lead, controlling a half-clearance superbly on his chest before angling in a volley past Stojkovic.
Four minutes later Nasri made the game safe, rounding off slick interplay between Nicklas Bendtner and Alex Song to finish coolly.
The only sour note for Arsenal came five minutes from time when Bacary Sagna received a straight red card for a professional foul on Aleksandar Lazevski on the edge of the area.