AC Milan were rumoured to be watching Joe Campbell for Arsenal on Saturday, but it was another young forward who stole the headlines - Yaya Sanogo had a good day and scored four of the goals that sunk a sorry looking Benfica, who after reaching the Europa League final last season and achieving a domestic treble have seen an exodus of star players that only Southampton can probably empathise with. Joe Campbell got the other goal for Arsenal and Alexis Sanchez made his first appearance in an Arsenal shirt towards the end.
Sanogo opened the scoring on 27 minutes when he converted an Aaron Ramsey cross. On 41 minutes Joel Campbell doubled the Gunners lead with a volleyed shot home. Benfica's defence were looking beleaguered and pretty flat. Before the break they didn't manage to track Sanogo a further 2 times and the young striker rounded off the first half with a hat-trick.
The second half didn't start off much better for the Portuguese side, but got even better for Sanogo, who after just 2 minutes scored his fourth and Arsenal's 5th. Moraes Artur in goals for Benfica was to blame on this occasion when he messed up a save from a Ramsay shot spilling it to a grateful Sanogo.
Nicvo Gaitan scored a consolation goal for Benfica with a header on 62 minutes for Benfica, but by now Arsenal were cruising. Alexis Sanchez came on for his Arsenal debut with about 20 minutes left and ran rings around Benfica with sublime goals, but there was no need for the Gunners to rub salt into the wounds.