Nigeria reach semifinals after pitch invasion LAGOS, Feb 7 (Reuters) - Jubilant Nigerian fans invaded the pitch and caused play to be delayed for 10 minutes as their team came from behind to beat Senegal 2-1 in extra time and reach the African Nations Cup semifinals on Monday. Nervous Senegalese players refused to return to the field after being engulfed by a mob of fans, who rushed on to the field after 18-year-old subsitute Julius Aghahowa gave Nigeria a 2-1 lead in the second minute of extra time. The golden goal rule is not used in the competition. Police seemed slow to react and Senegal at one stage appeared to walk towards their dressing room before finally agreeing to return to the field. Aghahowa had also scored Nigeria's equaliser six minutes from time after a superb goal by Senegal's Kalidou Fadiga early on had threatened a major upset. Nigeria's Austin Okocha was sent off for clashing with a defender in extra time. From Daily Soccer