Europa League: Four conclusions as Arsenal knock out Napoli 

#1 A disciplined performance from Arsenal

S.S.C. Napoli v Arsenal - UEFA Europa League Quarter Final: Second Leg

When was the last time you saw Arsenal keep back to back away clean sheets? Exactly. They faced two very attacking-minded teams in their last two away games, and the Gunners ran out as winners with clean sheets to their name as well.

Only one Arsenal player was given a yellow card last night and that was Arsenal's goalkeeper, Petr Cech, for allegedly wasting time during the goal kick. This tells us that Arsenal defended their goal with ease, despite the fact that they had to pit their wits against a side who scored past both Liverpool and PSG at the San Paulo.

Unai Emery and Arsenal have sealed a place in the semi-finals of the Europa League, and their next opponent is Valencia. The first leg will be at home, but this time, Emery's men will have to win the first leg with a better margin in order to book a berth in the final at Baku, as Valencia are not an easy side to defend against.