RB Leipzig have rejected Arsenal's offer of £55m for Dayot Upamecano, according to reports.
Unai Emery is desperate to add a new defender to his ranks before August 8.
Celtic left-back Kieran Tierney is also a target for Emery, but signing a central defender would be equally as satisfying.
The Gunners have tried and failed with an ambitious bid for 20-year-old Upamecano, according to German publication Bild.
The Frenchman has a release clause of £92m, but Leipzig would accept an offer of £70m.
