Arsene Wenger admits a 1-1 first-leg draw with Atletico Madrid was just about the worst possible result for his Arsenal side from their Europa League semi-final.

The visitors were on the back foot for almost the entire game after defender Sime Vrsaljko was dismissed for two yellow cards in the first 10 minutes.

Alexandre Lacazette eventually nodded home a cross from Jack Wilshere in the second half to reward the hosts for a long and probing assault on Atletico’s well drilled defence.

Arsenal were left reeling with eight minutes remaining when Antoine Griezmann latched on to a long ball forward, shrugged off Laurent Koscielny and stabbed into the net to give Diego Simeone’s men parity and a priceless away goal.

Wenger’s side must now breach an Atletico defence that has conceded just four times at home in La Liga this season if they are to permit Wenger’s 22-season spell in charge to end in the Europa League final on May 16.

While disappointed with the outcome, Wenger says Arsenal must retain their belief going to the Spanish capital.

“Looking at the performance and the way the game went, it was the worst possible result for us, but we have to go there in a positive mood and qualify,” Wenger conceded afterwards.

“Of course it feels like an opportunity missed. We could have qualified tonight but it didn’t happen. Their keeper made a lot of saves and they showed their quality by scoring with one chance.

“What matters is that we go there with the belief to do it.” Arsenal are now 6.00 to win the Europa League, while Atletico are strong favourites at 1.73.