In pics: women's 4X400m relay at 2019 IAAF World Athletics Championships

Sydney McLaughlin (1st R, bottom) of the United States passes the baton to her teammate Dalilah Muhammad (2nd R, bottom) during the women's 4X400m relay at the 2019 IAAF World Athletics Championships in Doha, Qatar, Oct. 6, 2019. (Xinhua/Wang Jingqiang)