Kepa wabaye umunyezamu wa mbere Chelsea iguze amafaranga menshi cyane kurusha abandi - miliyoni 71 z'amapawundi - ubwo yayigeragamo mu kwezi kwa munani k'umwaka ushize wa 2018 avuye muri Athletic Bilbao, yirengagije umutoza we Sarri washakaga kumusimbuza Caballero.
