Jack Wilshere scored two goals, the first after only 27 seconds, as Arsenal beat Marseille 2-0 on Tuesday to move to within touching distance of the Champions League last 16.
Meanwhile, Chelsea reached the knockout stages despite being beaten 1-0 by Swiss side Basel in their penultimate group game.
The 2012 champions went through because Schalke 04 could only draw 0-0 in Romania against Steaua Bucharest which leaves them on seven points, Basel on eight and Chelsea on nine.
However, Basel and Schalke clash in the final group game which means only one of them could overhaul Chelsea.
Wilshere rewarded Arsenal’s dominance with a second goal in the 65th minute, after Mesut Ozil had seen a penalty saved, to leave Arsene Wenger’s side three points clear of Borussia Dortmund and Napoli at the top of Group F.
Arsenal can now secure their progress to the knockout rounds for the 11th successive season by avoiding defeat in their final group game at Napoli on December 11.
However, Napoli’s loss to Dortmund in Tuesday’s other group game means that should Arsenal lose in Naples, and Dortmund win in Marseille, qualification would be decided by goal difference in the three games between Arsenal, Dortmund and Napoli.
Last season’s finalists Borussia Dortmund breathed life into their hopes of reaching the Champions League knock-out phase with a nervous 3-1 home win over Napoli.
Ajax gave their chances of qualifying for the Champions League last 16 a huge boost as they beat Barcelona 2-1 on Tuesday despite playing almost the entire second-half with 10 men.