Arsenal secured an impressive 2-0 win over Napoli in the first leg of their UEFA Europa League quarter-final at the Emirates Stadium on Thursday.
A strike from Aaron Ramsey and a Kalidou Koulibaly own goal have put Unai Emery's side in charge of the tie ahead of the second leg in Napoli on Thursday.
Chelsea were also victorious in their match against Slavia Prague. Maurizio Sarri's side were not at their best but won 1-0 in the Czech Republic thanks to a late Marcos Alonso header.
Benfica will also be confident of a place in the semi-finals after a 4-2 win over Eintracht Frankfurt, while two late goals saw Valencia beat La Liga rivals Villarreal 3-1.