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Event #2 - High Jump
Defending Olympic gold medalist Nafissatou Thiam surged into the heptathlon lead with an unmatched high jump mark of 1.92m (6 ft, 3.6 in), good enough 78 points more than any other athlete in the event.
She did not even attempt a jump until 1.80m, after several of the 23 competitors had already been eliminated. Her only misses came when trying to elevate the mark to 1.95m.
American Erica Bougard and Great Britain's defending world champion Katarina Johnson-Thompson both notched the next-best result at 1.86m (6 ft, 1.2 in).
The leader after the 100m hurdles, American Kendell Williams, finished in an eight-way tie for eighth place in the high jump with a mark of 1.80m, dropping her to the fifth position overall.
TOP 5 AFTER HIGH JUMP (2/7)
Nafissatou Thiam (BEL) - 2176
Erica Bougard (USA) - 2157
Katarina Johnson-Thompson (GBR) - 2138
Noor Vidts (BEL) - 2115
Kendell Williams (USA) - 2107
Event #1 - 100m Hurdles
American Kendell Williams went out to an early lead in the event with the top time in the 100m hurdles of 12.97 out of Heat 3, which produced the four fastest times overall.
The opening event is one of Williams' strongest, and also one of the weakest for defending Olympic gold medalist Nafissatou Thiam of Belgium, who relies primarily on her jumping and throwing ability to post big scores.
Thiam finished with the 15th-best time in the event at 13.54. Great Britain's defending world champion, Katarina Johnson-Thompson, secured a solid seventh place start in 13.27.
TOP 5 AFTER 100m HURDLES (1/7)
Kendell Williams (USA) - 1129
Marthe Koala (BUR) - 1114
Anouk Vetter (NED) - 1111
Erica Bougard (USA) - 1103
Noor Vidts (BEL) - 1099