Paraguayan tennis player Adolfo Daniel Vallejo is facing a "significant sanction" from French Open organisers after suggesting his second-round match should not have been umpired by a woman. Following his five-set defeat, Vallejo was quoted by Clay magazine as saying: "This sort of match needs to be umpired by a man, it’s very difficult for a woman to do it." Tournament organisers swiftly condemned the remarks on Friday, issuing a strong statement that deemed Vallejo’s comments "unacceptable". Vallejo claimed his match should not have been umpired by a female (Reuters) The French Tennis Federation and Roland Garros organisers asserted: "The competence of an umpire is not determined by their gender but by their professionalism and ability to officiate at the highest level.…