A spectacular hat-trick from striker Olivier Giroud helped Arsenal beat rivals Olympiakos 3-0 last night, and ensure qualification for the last 16 of the Champions League.
The Gunners needing to win by two clear goals to take second spot in Group F behind leaders Bayern Munich.
Giroud headed in the first goal at the near post and slotted home a second thanks to a well placed pass from Joel Campbell.
Arsenal were guaranteed their spot in the knockout stages when Giroud stepped up to convert a penalty, making it the striker's first hat-trick for the club.
Chelsea, who have struggled with their league form this season, topped their group with a convincing 2-0 win over FC Porto.
Porto needed a win themselves to ensure qualification, but rarely threatened Jose Mourinho's men.
Winning their group means the Blues will avoid big sides like Barcelona, Real Madrid and Bayern Munich when the last-16 draw is made on Monday.