Arsenal veteran Laurent Koscielny is desperate to make up for lost time this season.

Koscielny returns to the Europa League semis in Thursday's first leg at the Emirates, claiming his horror injury sustained at this stage last year changed his outlook on life.

The defender missed France's World Cup triumph in Russia after damaging his Achilles tendon in the last four clash with Atletico Madrid. Now the Gunners are back to the semi-finals against a different Spanish team – Valencia – as they bid to win their first European trophy since 1994.

Koscielny, who didn't return to action until December, recalled: “For me it was a bad moment in my career and my life. You grow up as a football player and a man. You fight with yourself, because you are a competititor.

"I did this for seven months. It is not about my age or my injury. It was a big challenge to fight against my injury and I think I did well. I am positive with this. It is a new semi-final against a new Spanish team. My life now is with this moment and I need to live with it. Now it is OK."

Asked what he had learned during his absence, Koscielny added: “I think sometimes you are focused on small things. It is not dangerous but it is not good for you. It is a difficult experience but I loved it because sometimes your eyes are opened more than before. When you don't know the injury, it is difficult.

“Now it is OK, it is behind me and I am very positive about where I am. I always fight for my club and my family."