By William Oyo-Ita 23 Feb 2016
The home side's Alex Oxlade-Chamberlain had a 10-yard shot blocked early on before Luis Suarez headed wide from close range for the visitors.
Gunners keeper Petr Cech blocked a Neymar strike and Olivier Giroud went close with a header at the other end.
But Neymar and Suarez combined to set up Messi to calmly slot inand the Argentine also scored a late penalty.
