TOKYO: Jamaica’s Elaine Thompson-Herah equalled the second-fastest time in history to retain her women’s Olympic 100m title on Saturday as ongoing mental health problems left gymnastics superstar Simone Biles’s Tokyo campaign teetering on the brink.Thompson-Herah blazed to an Olympic-record 10.61sec, well ahead of crestfallen two-time winner Shelly-Ann Fraser-Pryce, with Shericka Jackson completing an all-Jamaican podium.“I am really excited to come back and retain my title. My chest...