Arsenal and Chelsea have both progressed to the Europa League semi-finals.

The Gunners went into their away game at Napoli, holding a 2-0 lead.

They extended that aggregate advantage in southern Italy as Alexandre Lacazette's free-kick sealed a 1-0 win.

Napoli goalkeeper Alex Meret looks dejected after Arsenal's Alexandre Lacazette (far right) celebrates scoring his side's first goal of the game during the UEFA Europa League quarter final second leg match at the San Paolo Stadium, Naples.

Unai Emery's side now go on to face Valencia, who beat Valencia 2-0 at the Mestalla.

Valencia had already beaten Villarreal 3-1 in the away leg.

Fight Back

Chelsea held a 1-0 lead over Slavia Prague heading into tonight's second leg in London.

The Blues raced into a 4-1 lead over the Czech side with Pedro's brace the main contribution, along with Olivier Giroud and an own goal.

Slavia staged a second half fight-back however, through Petr Sevcik's double to leave the final scores at 4-3.

Chelsea's Olivier Giroud, the Europa League's top scorer, right, celebrates scoring his side's third goal during the Europa League quarterfinal, second leg, soccer match between Chelsea and Slavia Prague at Stamford Bridge stadium in London, Thursday, April 18, 2019. (AP Photo/Matt Dunham)

Maurizio Sarri's side now go on to play Eintracht Frankfurt.

The Bundesliga side had lost 4-2 at Benfica last week. But a 2-0 win tonight in Germany put Eintracht into the semis.