Saka injured as Lens beats Arsenal 2-1 in Champions League shock
- Arsenal suffered first defeat of the season against Lens in Champions League match.
- Key player Bukayo Saka went off injured in the first half for Arsenal.
- Lens striker Elye Wahi scored one goal and assisted another in the 2-1 win.
- Arsenal manager Arteta expressed concern over Saka's injury before Man City clash.
- Victory puts Lens top of Champions League Group B on 4 points ahead of Arsenal's 3.