The United States had a tough going in the men's 400m semifinals this afternoon at the IAAF World Championships, as NCAA record holder Fred Kerley was the lone American to advance to the final to be held on Tuesday evening in London. 

The fastest time of the day came from Kerley's section one, where 21-year-old Steven Gardiner broke his own Bahamian national record to win in 43.89. Kerley was the quickest man to 250m, but tied up down the homestretch as Gardiner and Jamaica's Nathon Allen -- a freshman at Auburn this past year -- beat him to the finish. Kerley ran 44.51 for third and would be the fastest time qualifier.

LaShawn Merritt of the United States, a two-time world champion over 400m, qualified to worlds based on his status as the 2016 Diamond League champion. The 31-year-old got out well in section two, but appeared to lose his cool once world record holder Wayde van Niekerk passed him. He tied up down the homestretch and finished just seventh in his section with a time of 45.52.

Men's 400m finalists:

RANK	ATHLETE	COUNTRY	MARK
1	Steven Gardiner	Bahamas	43.89Q
2	Nathon Allen	Jamaica	44.19Q
3	Wayde van Niekerk	South Africa	44.22Q
4	Isaac Makwala	Botswana	44.30Q
5	Baboloki Thebe	Botswana	44.33Q
6	Fred Kerley	USA	44.51Q
7	Demish Gaye	Jamaica	44.55Q
8	Abdalelah Haroun	Qatar	44.64Q