The clock stationed just past the finish line flashed 10.60 seconds and the letters ¡°NEW OR,¡± meaning ¡°new Olympic record,¡± when Elaine Thompson-Herah of Jamaica won the women¡¯s 100 meters on Saturday night.

Thompson-Herah had not only retained the 100-meter Olympic title she won in Rio de Janeiro in 2016, but she had done so by shattering Florence Griffith Joyner¡¯s record set in 1988. (Thompson-Herah¡¯s official time in the record books is 10.61.)

One day later, Lamont Marcell Jacobs of Italy produced an even more stunning time ¡ª 9.80 seconds ¡ª to win the men¡¯s 100, becoming the surprise winner of the race to supplant Usain Bolt as the world¡¯s fastest man. Jacobs was little known before storming to the fastest time in an Olympic final by a man not named Bolt.