Arsenal were held by Marseille, leaving them a point clear of the French side at the top of Champions League Group F.
It was the first time in three years that the Gunners failed to score at home in a Champions League match.
Marseille started well with Andre Ayew and Loic Remy shooting wide, but the London side improved as Theo Walcott and Gervinho had drives kept out.
Robin van Persie came on for Arsenal in the 61st minute, but could not make an impact in a low-key second half.
Full report follows.