The 5-foot-10 Jones suffered a stress fracture in his lower leg and had it seen by doctors on Thursday morning. U of L confirmed the injury later in the day.
"Major blow, man," Jones said on Instagram.
Expected to be one of the starting guards, Jones had lost weight and was at around 170 pounds. He participated in adidas Nations last week and said he felt "as good as ever."
Jones helped the Cardinals to the Sweet 16 last season, his first after coming to U of L from Northwest Florida Junior College.
Sophomore forward Akoy Agau is also sidelined after having hernia surgery.