Aubameyang, Dembele and Traore train with Barcelona ahead of Napoli game - in pictures

Mighty Barcelona will be given a humbling reality check on Thursday when they begin their bid to win the second-tier Europa League.

The five-time European champions crashed out of the Champions League in the group stage with just two goals scored in six matches as they finished third behind Bayern Munich and Benfica.

At least their opponents in a competition Barca are taking part in for the first time in 18 years offer a bit of Euro glamour, as they take on Serie A title challengers Napoli at Camp Nou. The two teams met in the last 16 of the Champions League only two years ago.

It will be a sign of some progress under manager Xavi Hernandez if Barca can emerge victorious in the two-legged play-off to reach the last-16 stage.

Barca were busy in the last transfer window bringing in the likes of Ferran Torres, Adama Traore and Pierre-Emerick Aubameyang - and the attacking trio were all training on Wednesday ahead of the play-off first leg.

And Xavi has backed former Arsenal striker Aubameyang to make his mark. "He's good, and he trains really well. He's 100 per cent ready. He's a player who can make a difference, he works well in spaces and makes good runs into the area," Xavi said.

"He's put in performances in recent years that have been very good. I'm very happy with him, he's working positively in our group, and he's very professional."

They currently sit fourth in La Liga, a whopping 15 points behind leaders Real Madrid, and drew 2-2 at neighbours Espanyol on Sunday after Luuk de Jong's injury-time goal rescued a point.

Napoli, managed by Luciano Spalletti, finished second but joint top of their Europa League group level on points with Spartak Moscow. They are third in Serie A - two points behind leaders AC Milan - and