London - American Phyllis Francis ripped up the form book to claim a shock gold in the women's 400m at the IAAF World Championships on Wednesday.
The race had been billed as a straight duel between multi-medalled American Allyson Felix, the defending champion, and Olympic champion Shaunae Miller-Uibo.
But clear leader Miller-Uibo tied up in shocking fashion with 20 metres to run to allow hard-charging Francis, 25, win with a personal best of 49.92 seconds.
Bahrain teenager Salwa Eid Naser claimed silver in a national record of 50.06, with Felix taking bronze, just 0.02sec adrift, as Miller-Uibo went from first to fourth in the final strides.
IAAF World Championships finals results on Wednesday:
Men
400m hurdles
1. Karsten Warholm (NOR) 48.35 seconds
2. Yasmani Copello (TUR) 48.49
3. Kerron Clement (USA) 48.52
4. Kemar Mowatt (JAM) 48.99
5. TJ Holmes (USA) 49.00
6. Juander Sanotos (DOM) 49.04
7. Abderrahaman Samba (QAT) 49.74
8. Kariem Hussein (SUI) 50.07
Women
400m
1. Phyllis Francis (USA) 48.92 seconds
2. Salwa Eid Naser (BRN) 50.06
3. Allyson Felix (USA) 50.08
4. Shaunae Miller-Uibo (BAH) 50.49
5. Sheicka Jackson (JAM) 50.76
6. Stephenie Ann McPherson (JAM) 50.86
7. Kabange Mupopo (ZAM) 51.15
8. Novlene Williams-Mills (JAM) 51.48
Shot put
1. Lijiao Gong (DHN) 19.94 metres
2. Anita Marton (HUN) 19.49
3. Michelle Carter (USA) 19.14
4. Danniel Thomas-Dodd (JAM) 18.91
5. Yang Gao (CHN) 18.25
6. Brittany Crew (CAN) 18.21
7. Yuliya Leantsiuk (BLR) 18.12
8. Yaniuvis Lopez (CUB) 18.03