Arsenal boss Mikel Arteta admits he has concerns with Leandro Trossard's injury.

Trossard broke down during victory over Bournemouth.

Arteta said: "It is a worry. He came to me straight away and told me he could not continue because he'd felt something when he was tracking back after the corner. We have to assess him and see how he is."

On if Gabriel Martinelli is set to move centrally to cover the Belgian, he added: "The way they were defending, we thought it was the best way to do it. We have alternatives - Emile can play in that position as well, we can move players and Reiss can give us width and threat in wider areas.

"We'll have to assess every opponent because they'll be different. Now we have Sporting CP, a really tough match, so let's hope we'll have one or two back."