A pole vault athlete pictured in action at the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO DIRK WAEM

Great Britain Laura Muir reacts after the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO JASPER JACOBS

Belgian Nafissatou Nafi Thiam celebrates after winning the women's high jump event during the 2018 edition of the AG Insurance Memorial Van Damme IAAF Diamond League athletics meeting, Friday 31 August 2018 in Brussels. BELGA PHOTO LAURIE DIEFFEMBACQ