Arsenal veteran Per Mertesacker is set to return for their clash with Southampton.

Germany international Shkodran Mustafi was forced off early on in last weekend's 3-1 defeat by Manchester United and will sit out the game at St Mary's.

The 25-year-old has looked more secure in the three-man defence Arsene Wenger has largely fielded since early in the year.

"It is a possibility," Wenger said earlier in the week when asked if Mustafi could play at Southampton.

"It is a little thigh problem. A small one."

But reports suggest Mustafi will definitely miss the game on the south coast.