A clutch of outstanding sprint performances highlighted the US Junior Championships, which concluded on Sunday (26) after three days of action in Clovis, California.
The most notable of all of the weekend's performances came in one of the preliminary rounds.
Running in the heats of the 100m hurdles, 15-year-old Tia Jones clocked a sensational 12.84 to equal* the existing world U20 record set by Cuba's Aliuska Lopez in 1987.
Tobi Amusan of Nigeria clocked 12.83 in El Paso on 30 April, but that mark won’t be ratified as there was no post-race drugs test and a 12.74 clocking by USA's Dior Hall in 2015 was not ratified as a world U20 record for the same reason.
Jones, whose time was also a world U18 best and a world age-15 best, will be still young enough to compete at the IAAF World U18 Championships Nairobi 2017 and will still be a junior up to and including 2019.
Much of her speed carried over to the final, but there she was surprisingly nipped at the line by Alexis Duncan by a scant 0.01, 13.04 to 13.05.
It was a personal best for the 17-year-old Duncan, who will now be targeting a podium finish at the IAAF World U20 Championships Bydgoszcz 2016 to make up for a disappointing seventh place finish at last year's IAAF World U18 Championships in Cali where she started among the favourites.
Sydney McLaughlin's high powered momentum continued with her 54.54 400m hurdles victory, just outside the 54.46 world U18 best she ran on 19 June.
"I was nervous for the first one hundred, I didn’t get out as I wanted to, but as the race went on I got back to my place and finished well," McLaughlin said. "This was a good way to get back and run another 54 and get that under my belt."
Next stop for the 16-year-old world youth champion will be the US Olympic Trials where she'll be aiming to become one of the youngest ever track and field Olympians.
Her brother Tyler will also be joining her on the team for the World U20 Championships after he won the men's 400m hurdles in 50.74.
Hill and Lyles impress in 100m
Sprinters Candace Hill and Noah Lyles produced impressive 100m performances to highlight the first day's action.
Hill, the world youth 100m and 200m champion and still just 17, blazed through the opening round in 11.09, the fastest U20 performance in the world this year, before dominating the final in 11.24. Jayla Kirkland edge Celera Barnes in a tight battle for second, each credited with 11.41.
"It wasn’t the best race for me but I’m pleased," said Hill, who entered the weekend with an 11.19 season's best. "It feels amazing, I came out here, this was my goal [to qualify for the IAAF World U20 Championships] and make the team in the 100."
Hill made waves last year when she clocked 10.98 at age 16 to become the youngest girl to run under 11 seconds in the event.
After winning her 200m heat in 22.76, Hill didn't start for the final. In her absence, the title went to Kirkland in 23.16.
In the men's 100m, Lyles was as dominant as Hill was, running away with the title in 10.08. His performance was assisted by a 2.2m/s tailwind, just beyond the 2.0m/s allowable for record purposes.
"It felt pretty nice, this is my first time in three weeks getting back to racing, so I’m just trying to get race sharp and everything," said the 18-year-old from Alexandria, Virginia, a member of the winning medley relay at last year's IAAF World U18 Championships in Cali.
All-round sprint talent Michael Norman broke the championship record in the 200m. The 18-year-old won by a comfortable margin of 0.62 to win in 20.15, moving to sixth on the world U20 all-time list. Norman, who also has a 400m PB of 45.19, will now shift his focus to the US Olympic Trials.
Just three hundredths separated Will London and Kahmari Montgomery in the men’s 400m, with London taking the title in 45.61.
Two days after finishing fifth in the 100m, world youth silver medallist Lynna Irby convincingly won the 400m in 52.51.
World U20 leads from Krah and Matthews
Marcus Krah cruised to an impressive victory in the 110m hurdles, clocking 13.25, also the fastest in the world by a U20 athlete this season and just outside the event’s world all-time top-10 list.
"My form going over, my start, my finish, my quickness over the hurdles, just felt great,” said Krah, who clocked his previous personal best of 13.32 five weeks ago.
In a competitive race, Amere Lattin was second in 13.32, also a career best.
Chris Nilsen topped 5.50m on his third attempt to take the pole vault title over Deakin Volz, who cleared a personal best of 5.45m.
"One of the biggest things in pole vault is to stay consistent," Nilsen said. "This is my sixth time over 18 feet (5.48m) in a meet, so I’m happy to represent myself and stay consistent."
World youth champion Sammy Watson won a close 800m in a PB of 2:02.91 to finish just five hundredths ahead of Aaliyah Miller.
Alexa Efraimson produced a dominant display in the 1500m, the event in which she holds the North American U20 record. She won in 4:16.75 to finish more than a second ahead of her nearest rival.
In other action, Jamari Ward won the men's long jump with a 7.84m personal best and Bria Matthews won the long jump at 6.49m, the best jump by a U20 athlete in the world this season.
Fiona O'Keefe won a close women's 5000m over Anna Rohrer 15:56.84 to 15:57.92, personal bests for both, and Kate Murphy won the 3000m in 9:10.51.
On the men's side, world youth champion Adrian Piperi won the shot put with 20.18m, his first time using the junior 6kg implement in competition. Vincent Crisp won the 800m in 1:46.97 and Charles Brown Jr took the triple jump with 16.35m.
Bob Ramsak for the IAAF
*pending the usual ratification procedures