Richardson, who powered to an impressive victory in the 100m on Saturday, barely got out of second gear as she coasted through her opening 200m heat in 21.99sec at Hayward Field in Eugene.

Tokyo Olympic 200m bronze medallist Gabby Thomas was second quickest behind Richardson in a time of 22.11sec while Abby Steiner was third fastest in 22.29sec.

"My biggest thing is execution, so I'm just really focusing on executing the curve to make the straight much easier," said Richardson. "I feel like I did that well today, but I have room for improvement."

Richardson brushed off suggestions that with her ticket to Paris already assured following her 100m win last weekend, that the pressure was off.

"Absolutely not," she said. "I feel like any time I touch the track it's an opportunity for me to work on my best stuff and be my best self. So every time I touch the track there's pressure."

In the men's 200m, meanwhile, Lyles showed no sign of rust from his 100m victory on Sunday as he glided through his heat in 20.10sec.

There was a similarly assured performance by reigning 400m hurdles Olympic champion and world record holder McLaughlin-Levrone, who hardly broke sweat as she sauntered through her opening heat in 53.07sec.

McLaughlin-Levrone crossed the line around 20m clear of her nearest rival in a time of 53.07sec.

"It felt good," McLaughlin-Levrone said. "I'm just excited to be out here, shake off the nerves. Stride pattern felt good -- just getting a feel of the nerves again.

"So I really felt good."

In the men's 110m hurdles, meanwhile, three-time world champion Grant Holloway continued his serene progress towards an Olympic berth by clocking 12.96sec.

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