Updated

Trayvon Bromell is making bold predictions for the junior world track championships this week.

The Baylor freshman set a junior world record in the 100 meters at the NCAA track and field championships last month. He broke the 10-second barrier, running in 9.97 at Hayward Field.

Oregon's historic track facility is also hosting the IAAF world junior championships — marking the first time the event has been held in the United States — starting Tuesday. Nearly 1,600 athletes from 170 countries will take part in the six-day event which runs through Sunday. Most finals are set for this weekend.

Hayward Field also recently hosted the U.S. junior championships earlier this month, with the top finishers there moving on to worlds.

After breaking the world junior record at the NCAA championships, becoming the first freshman to win the 100 since Florida State's Walter Dix in 2005, Bromell went on to win gold at the U.S. juniors in 10.07.

"I feel like I've got a lot more," he told reporters gathered at a preview event in Eugene on Monday. "I'm not going to run any slower. My heart won't let me."

Bromell's 9.97 at the NCAA championships bested the junior record of 10.01 that he himself matched earlier in the year at the Texas Relays.

Also taking part in the junior worlds is teenage phenom Mary Cain, who will run in the 3,000 meters. She won the event at the U.S. championships in 9 minutes, 15.81 seconds for a spot at worlds.

Cain made the finals in the 1,500 at the senior world outdoor championships last year in Moscow, at 17 becoming the youngest woman to run the event.

"I chose the 3,000 meters because I thought it would be fun to mix it up," Cain said Monday.

Cain eschewed a college track career and decided to join the Nike Oregon Project, training under decorated U.S. marathoner Alberto Salazar. The 18-year-old plans to study — just not compete as an athlete — at the University of Portland.

The U.S. team also includes sprinter Kaylin Whitney, an incoming junior at East Ridge High School in Clermont, Florida, who will run in both the 100 and 200 meters.

Earlier this month at the U.S. junior championships, Whitney broke the world junior record by running the 200 meters in 22.49 seconds.

The 16-year-old bested the world 17-and-under mark of 22.58 set by Marion Jones in 1992. Whitney also surpassed the prep low-altitude mark of 22.51, set by Allyson Felix at the 2003 Mount SAC Relays.

She also set a high school record of 11.10 in the 100.

The event, sanctioned by the sport's international governing body, includes athletes born between 1995 and 1998. Countries can enter two athletes in each event.