Arsene Wenger's Arsenal will play the first leg at the Emirates Stadium
Arsenal will face Atletico Madrid in the semi-finals of the Europa League in a mouth-watering clash of two big clubs that have taken a backseat in their domestic leagues in recent years.
French club Marseille will play FC Salzburg, a club backed by soft drinks giant Red Bull, in the other semi-final.
Arsene Wenger's Arsenal will play the first leg at the Emirates Stadium against Atletico, led by French striker Antoine Griezmann, who are favourites to win the competition for the third time.
Wenger, whose side play Man United away in the Premier League between the two semi-final legs, had identified Atletico, Champions League finalists in 2014 and 2016, as the most dangerous side in the draw.
"Everybody speaks about Atletico Madrid that they look the strongest team on paper," he said, but he also described Marseille as a difficult place to go.
The first legs will take place on April 26 with the second on May 3.
"They are a similar kind of club to us," Atletico Madrid director Clemente Villaverde said at the draw in Nyon.
"Arsenal are a great team, they're up there every year fighting for trophies and getting deep into their European competitions," he said.
Arsenal reached the last four of the Europa League after surviving a scare against CSKA Moscow in Thursday's quarter-final second leg in the Russian capital.
Danny Welbeck and Aaron Ramsey both scored late in the game for Arsenal to calm nerves after CSKA had raced into a 2-0 lead on the night. The London side won 6-3 on aggregate.
Atletico lost 1-0 to Sporting in Lisbon on Thursday but advanced 2-1 on aggregate.
British bookmakers William Hills make Madrid hot favourites to win the competition, but explained why Arsenal fans still have reason for optimism.
"It could be argued that Arsenal need this more than Atletico as a route into the Champions League next season," said William Hill spokesman Joe Crilly.
"Their Europa League form has been in stark contrast to their Premier League form during the second half of this season and they have every chance of progressing," Crilly said.
Marseille overcame a first-leg deficit to beat German side Leipzig 5-3 over two legs in their quarter-final, while 1994 finalists Salzburg produced the shock result of the night by defeating Italian side Lazio 4-1 at home to win 6-5 on aggregate.
Salzburg have already beaten Marseille once in the competition this season, a 1-0 victory in Austria. The teams also drew 0-0 at the Velodrome.
"But this time it's the semi-final so it'll be different," Marseille director Andoni Zubizarreta told beIN Sports.
The former Spain goalkeeper refused to accept it was an easy draw however.
"The four clubs have worked a lot to reach the semi-finals and yesterday Salzburg was very strong against Lazio," Zubizarreta insisted in reference to the four goals Salzburg hit past the Romans on Thursday.