The Manchester City striker suffered a muscular injury against Real Madrid which could keep him out of the Chelsea clash.
The 21-year-old Brit has returned to form but now faces the world No1 in the last eight in Stuttgart
Mikel Arteta has urged Arsenal to prove they have the mental strength to bounce back from a painful spell that wrecked their Champions League challenge and dented their Premier League title bid.Chasing Arsenal's first Premier League crown in 20 years after blowing an eight-point lead in the title race last season, Arteta knows the verdict will not be kind if his team finish empty-handed again.