The steely McLaughlin took the immediate lead in a clinical performance before breaking the tape just shy of the US record, with Britton Wilson finishing five hundredths of a second behind and Talitha Diggs taking third place in 49.93.
McLaughlin took a chunk out of her own 400m hurdles world record to win the world title a year ago and will now have the opportunity to double up with the flat event at the world championships in Budapest, Hungary, which kick off on August 19.
“The greats always push themselves and I want to be one of them, so I have to push myself and get out of my comfort zone, so I’m just happy to be here,” a breathless McLaughlin said in a trackside televised interview.
Christian Coleman advanced in the men’s 200m heats in 20.06s, six hundredths of a second behind the fastest in the field Robert Gregory, a night after he finished second in the 100m final to book his ticket to Budapest.
Fred Kerley, who has an automatic spot at worlds as the reigning title-holder in the shorter distance, also moved on to Sunday’s 200m semifinal in 20.23s.
Twice world champion Grant Holloway easily advanced from the opening 110m hurdles heats in 13.07s while Devon Allen, a favourite in 2022 who was bounced from the competition due to a false start, moved on by the skin of his teeth in 13.51s.
The top three finishers across all events in Eugene who meet certain qualifying standards, as well as reigning global title-holders, will advance to the world championships.
The US championships wrap up on Sunday.
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