Arsene Wenger was left devastated by Arsenal's Europa League defeat to Atletico Madrid on Thursday but made a staunch defence of midfielder Mesut Ozil.

Ozil's performance was heavily criticised by former Arsenal defender Martin Keown, who said the German had cried "crocodile tears" after the game, and was "not fit to wear the shirt".

Diego Costa's strike proved decisive at the Wanda Metropolitano where a 1-0 victory secured Atletico a 2-1 win on aggregate and a place in the final against Marseille.

Defeat ends Wenger's hopes of leaving Arsenal on a high as his team missed out on a shot at a major trophy and squandered their last chance to qualify for the Champions League.

"I'm very sad tonight," Wenger said. "Unfortunately you have to go through that -- the game can be very cruel, sometimes very nice, but the suffering is very strong tonight.

"Looking at the chances over the two games the least we could say is we are very frustrated. The tie should have been over in the first game."

It remains to be seen how another season outside Europe's premier tournament will affect Arsenal's search both for a new coach, and new signings, this summer.

"The club now has to think about what to do for next season," Wenger said. "I think there are some good ingredients in our team and they will bounce back. With the right additions in the summer I think they can compete next year."

- 'We expect better' -

Keown, however, was less optimistic and reserved a particularly harsh assessment for Ozil.

"He wasn't fit to wear the shirt tonight," Keown told BT Sport. "I've seen this a lot this season and it needs to be said. He needs to be dug out. We expect better from him.

"These are crocodile tears I'm seeing from the player. He's not conning me."

Keown added: "I bet he doesn't play again this season. He'll have some emotional breakdown and won't play this weekend."

When Keown's comments were put to Wenger, he said: "I don't agree with that. You will see that he gave a lot. It was a difficult team, physically very intense.

"I'm convinced that Ozil should not be criticised by anyone just because he did not score. We had plenty of opportunities and we lose as a team."

Wenger also delivered an update on the fitness of Laurent Koscielny, who had to be carried off on a stretcher in the 12th minute after the defender went down, with nobody near him, clutching his left Achilles.

Arsenal and France now face an anxious wait.

"It doesn't look very good, it's his Achilles," Wenger said. "You can always hope for a miracle in the scan but if he has a ruptured Achilles, his chances for the World Cup are non-existent."

Costa was the star of the show, providing the tenacity and killer instinct Arsenal so desperately lacked.

"Costa came back here for nights like this," Atletico coach Diego Simeone said. "To be important, to lead from the front. This side needs an aggressive striker and that's exactly what he is."

Rolando extra-time strike edges Marseille into Europa League final

Marseille booked a Europa League final meeting with Atletico Madrid after Portuguese defender Rolando struck in extra time to grab a 3-2 aggregate victory over a spirited Salzburg on Thursday.

Salzburg produced a rousing second-half performance to wipe out a 2-0 first-leg deficit, but Marseille became the first French side to reach a European final since 2004 despite a 2-1 defeat on the night.

Amadou Haidara gave the dominant hosts hope early in the second half with an excellent individual effort before Bouna Sarr's own goal levelled the semi-final.

Rudi Garcia's visitors survived some late scares to force a further half-hour and substitute Rolando volleyed home a 116th-minute Dimitri Payet corner that shouldn't have been given.

The 20-year-old Haidara, the outstanding player on the night, was sent off as his frustrations boiled over, as Salzburg's incredible run which included wins over Borussia Dortmund and Lazio came to an end.

Marseille, runners-up to Valencia in the UEFA Cup 14 years ago, will make the short trip from their Stade Velodrome home to take on Atletico in the final in Lyon on May 16, after the Spaniards beat Arsenal in the other semi-final.

"We believed in it and in the end we managed to get everyone together, all the people of Marseille believed in us, we're in the final," defender Adil Rami, who won the tournament with Sevilla two years ago, told BeIN Sports.

"It's going to be a big game, we will have given a wonderful experience to all the people of Marseille and now we have to win this final."

Payet, who set up both of Marseille's first-leg goals, immediately provided a set-piece threat as his wicked delivery from a free-kick was turned over by Lucas Ocampos in the sixth minute.

Salzburg, knowing a Marseille away goal would all but end the tie, were cautious in the first half and failed to cause the visitors any real anxious moments, with their best effort a tame shot from Munas Dabbur straight at goalkeeper Yohann Pele -- playing with Steve Mandanda still out injured.

Haidara blows tie wide open

Marseille started strongly after the interval, with Ocampos and Valere Germain both going close, but Salzburg blew the tie wide open by breaking the deadlock in the 53rd minute.

Malian international Haidara burst forward and fired a low strike under the body of Pele to halve the deficit with his eighth goal of the season.

That goal gave the Austrians renewed hope and Pele had to be alert to beat away a venomous long-range strike from Brazilian centre-back Andre Ramalho.

The equaliser was coming and it duly arrived in the 65th minute with Haidara again playing his part as Marseille's defence capitulated.

The midfielder's low cross was miskicked by centre-back Rami straight to Xaver Schlager, whose sliced volley was turned into his own net by Sarr.

Salzburg, who also beat Marseille 1-0 at home in the group stage, had chances to move in front, as Croatian defender Duje Caleta-Car headed over and Pele sprung to his right to tip away a low drive from substitute Hwang Hee-chan.

Marseille came agonisingly close to booking a place in the final in normal time, but Florian Thauvin's header came back off the crossbar.

Both sides were nervy at the start of the extra 30 minutes, but Marseille were left indebted to their stand-in goalkeeper as Pele produced a magnificent one-handed save to keep out Caleta-Car's powerful header.

Rolando was sent on by Garcia to try and secure a penalty shoot-out, only to snatch a controversial winner.

A corner was awarded despite Andre-Frank Zambo Anguissa's shot appearing to strike a Marseille foot before flying behind, and the 32-year-old Rolando side-footed another dangerous Payet cross into the net.