Abdul Hakim Sani Brown tied his personal best in the men's 100 meters with a time of 10.05 seconds at the world athletics championships on Friday, advancing to the semifinals with fellow Japanese Shuhei Tada and Asuka Cambridge.
Tada clocked 10.19 and Cambridge at 10.21, as three sprinters reached the semis in the event for the first time at the worlds.
The 18-year-old Sani Brown finished first in his heat, tying his record that he set in June at the national athletics championships.
"I was worried that it is cold (in London) but my body moved fine," said Sani Brown. "I wasn't nervous at all that it made me wonder if I would be alright, but it was okay.
"I will refocus my mind and prepare for the semis."
Tada was fourth in his heat with Jamaican world record-holder Usain Bolt (10.07). "I was leading the first half of the race, and I thought I might be able to finish first, but I overstrained myself," said Tada.
Cambridge said, "I'm not really satisfied. I couldn't keep my form at the end."
At the semifinals on Saturday, Sani Brown will run alongside London Olympic silver medalist Yohan Blake of Jamaica. Tada is placed in the same heat with Bolt, who will retire at the end of the championships, and Cambridge is with American Justin Gatlin.