Ukraine's Vira Rebryk highlighted Thursday afternoon's session with a World Junior record in the women's javelin throw at the 12th IAAF World Junior Championships.
Rebryk, who achieved the mark – 63.01 metres on her second attempt, erased the previous record of 62.93m held by Chinese Li Zhang since 2003.
The 18-year-old Rebryk surprised herself, not with the win, but the record. "I expected to win, but I did not believe I would have set a world junior record," she said.
"I only did what my coach told me to do, and when I saw the mark, I was very happy," he added.
Chinese Lingwei Li finished second with a personal best throw of 59.25m while Serbia's Tatjana Jelaca was third with a national record throw of 58.77m.
Kenyan double in women’s steeplechase
Also in the afternoon session, barefooted Kenya's 3000 metres steeplechaser Christine Kambua Muyanga was impressive, archiving a Championship record.
Muyanga, who said, "I ran barefooted, because of an injury", was happy with her performance.
"I've never been at the World Junior Championships before, that is the reason my happiness is doubled…”
In what turned out to be an impressive run, Muyanga's personal best run of 9:31.356 erased her countrywoman Caroline Chepkurui Tuigong's record of 9:40.95.
Elizabeth Mueni, also of Kenya, finished second in the event in 9:36.50 and Ethiopian Korahubish Itaa, who ran a national record of 9:37.81 for third.
The event also saw Finland's Sandra Eriksson (10:00.87) and Chez Republic's Lucie Sekanova (10:16.31) archiving national records.
400 finals go to US and Nigeria
United States' Marcus Boyd won the men's 400m in 45.53 seconds ahead of Grenadian Kirani James (45.70) and O'Neal Wilder, also of United States (45.76).
Boyd was over happy for the victory, especially since he beat Wilder's world leading mark of 45.54.
"It was an advantage to have an outside lane," said Boyd, who ran out of lane eight. "I fell bad for O'Neal, but now I am the world leader," he added.
As for Wilder: "I' happy for an American victory"
He, however, explained the reason behind his bronze medal performance. "I was a little tight in coming into the race, but there's no single reason for why I don't win," he added.
The girls' event – 400m – went to Nigeria's Folashade Abugan in 51.84 seconds. Abugan, who led off the curve, held off the fast finishing Jessica Beard of United States (52.09) and Cuban Susana A. Clement (52.36).
Decathlon gold decided by only two points!
Germany's Jan Felix Knobel won the men's decathlon event with a combined points tally of 7896, a world leading mark.
Bulgaria's Eduard Mihan (7894 points) and Serbia's Mihail Dudas (7663), both national records, were second and third respectively.
And a double for Cuba
In the field, Cuban pair of Dailenys Alcantara and Josleidy Ribalta finished one-two with leaps of 14.25m, a world leading mark, and 13.85m respectively.
In the women's high jump final, Germany's Kimberly Jess cleared 1.86 metres to take gold, the same height as Bulgaria's Mirela Demireva, who was credited with second.
Jess said she was surprised with the result. "I expected a medal of some colour, but not the gold … I thought it would take 1.90 to win.
"I am overwhelmed and so happy," she added.
Belgium's Hannelore Desmet and Cuban Lesyani Mayor, who like the first and second finishers, leapt personal best of 1.86 for joint third.
Desmet was also happy with her performance. "I'm excited…I'm really happy that I achieved such a high position," she added.
A first for Chile
Natalie Duco of Chile took the women's shot put with a throw of 17.23 metres over Melissa Boekelman of Netherland (16.60m) and Chinese Qiao Ma (16.55m).
200m Semis conclude
Meanwhile, in the women's 200m semi-finals, Grenadian Janelle Redhead with 23.47 seconds, leads her competitors going into Friday's final.
"The race was very good," Redhead said. "I'm so satisfied that I am in the final," she added.
Sheniqua Ferguson, who will represent Bahamas at the Beijing Olympic this summer, had the second fastest time – 23.40 – for second in semi-final two behind Redhead.
Jamile Samuel of Netherland (23.57) and American Tiffany Townsend (23.65) are the other top qualifiers.
However, the top four on times, will be challenge in Friday's final by St Kitts and Nevis' Meritzer Williams, who was an easy winner in semi-final one.
"The race was pretty good," was how Williams described her semi-final. "I am just looking forward to a good final," she added.
Men’s 400m Hurdles final promises to be a US v RSA affair
In the men's event, American Curtis Mitchell with his personal best 20.74 leads Jamaican Nickel Ashmeade (20.83) and Christophe Lemaitre of France (20.88) going into Friday's final.
Curtis promised more in the final. "I am not done yet … I want the gold," he said.
Americans Jeshua Anderson and Johnny Dutch, the world leader, booked their places in the men's 400m hurdles with the best times – 49.90 and 50.40 respectively.
However, the American duo leading competitors are Cornel Fredericks of South Africa (51.11) and Amaurys R. Valle of Cuba (51.17), but Anderson said the most important thing is a one-two finish in the final.
"It doesn't matter much which one of us win," Anderson said.
Anthony Foster for the IAAF