Trayvon Bromell surprised Noah Lyles in the 100m at the Oregon Relays in Eugene on Saturday (24 April).
Rio 2016 finalist Bromell showed strong form on the indoor athletics circuit this year, and made a blistering start on his 2021 outdoor debut as he took victory in 10.01s running into a slight headwind in cool conditions.
Lyles, the reigning world champion over 200m and gold medal favourite for Tokyo 2020, finished strongly to take second in 10.17s ahead of Liberia's Emmanuel Matadi, Michael Rogers and Divine Oduduru of Nigeria.
Shaunae Miller-Uibo showed why she is the reigning Olympic champion over 400m with a superb performance in the first meet at the redeveloped Hayward Field which will host next year's World Championships.
The Bahamian star was at her effortless best in clocking a world lead 49.08s with Lynna Irby a distant second ahead of fellow American Jessica Beard.
Miller-Uibo has said she will probably not defend her 400m title in Tokyo, preferring to concentrate instead on the 200m.
Rudy Winkler produced a big personal best and 2021 world lead in the men's hammer.
The 26-year-old from New York State recorded 80.70m last year and went even better today with a massive 81.98m, the best distance for over five years.
There was a surprise in the women's hammer as world champion DeAnna Price suffered her first defeat since May 2019.
Fellow American Brooke Andersen won with 77.99m as Price could only manage a best of 76.15m.
There was also a rare defeat for triple jump great Christian Taylor.
The two-time reigning Olympic champion was only third with 16.52m as Donald Scott (16.89m) took victory with Jamaica's Clive Pullen (16.55m) in second.
Michael Norman held off his training partner, 400m hurdles silver medallist Rai Benjamin, to take the flat 400m in 44.67s.
Jasmine Camacho-Quinn of Puerto Rico kept up her impressive form with a comfortable win in the 100m hurdles.
The 24-year-old clocked 12.32s last weekend to go seventh on the all-time list, and she won in 12.46s with Jamaica's Brittany Anderson a distant second from Taliyah Brooks.
World 400m hurdles silver medallist Sydney McLaughlin was fourth in 12.87s.
Reigning world 800m champion Donavan Brazier was third up in trip at 1500m with Oliver Hoare surging to victory from the front.
The Australian transferred his strong indoor form to outdoors, winning in a new personal best of 3:33.54 ahead of Justin Knight.
Britain's Laura Muir took the women's event in 4:01.54 ahead of Americans Helen Schlachtenhaufen and Cory McGee, with Rio 2016 bronze medallist Jenny Simpson back in ninth.
Nigeria's Blessing Okagbare won the women's 100m in 10.97s ahead of USA's Morolake Akinosun and Britain's Daryll Neita.
In a rare outing in the short sprint, Allyson Felix was seventh in 11.30s, the same time as reigning long jump Olympic champion and two-time sprint relay gold medallist Tianna Bartoletta.
Grenada's world champion Anderson Peters won the javelin with 82.72m.
On a busy day of athletics in the United States, Olympic champion Ryan Crouser set a new world lead in the men's shot at the Drake Relays in Des Moines, Iowa.
Crouser, who broke the indoor world record in January, threw 21.93m to maintain his unbeaten record which stretches back to the 2019 World Championships.
In Miami, 2019 world 400m bronze medallist Fred Kerley clocked the fastest time in the world this year... in the 100m.
Kerley won in 9.91s to join Wayde van Niekerk and Michael Norman as the only men to break 10 seconds for 100m and 44 seconds for 400m.