As a child, U.S. Olympian Christian Coleman dreamed of sharing a track with U.S. track stars Justin Gatlin and Tyson Gay. On Thursday, he got his chance — running the 4x100 meter relay preliminary heat with Gay.

“It is an experience of a lifetime,” Coleman said. “It is the highest stage you can get as a track athlete and to be here at such a young age, I am extremely blessed.”

Coleman ran the second leg of the heat. He kept the team on pace for a season-best mark of 37.65 seconds. The U.S. qualified in first place for the finals.

“It was crazy and huge crowd,” he said. “I had to calm my nerves and get the job done.”

Coleman, an Atlanta native who graduated from Our Lady of Mercy in Fairburn and is a standout at the University of Tennessee, has seen his life completely change — two months after not knowing if he would make the Olympics.

In July, he competed at the U.S. Olympic trials in Portland, Ore., and ran a time 10.06 seconds in the 100-meter dash. He would finish sixth, and he thought his Olympic dreams were over. It wasn’t until a phone call from his coach that his fortunes changed.

“I was in a hotel going back to Tennessee,” he said. “My coach called me and told me that they were going to bring me on for the relay pool, and I was extremely excited. It is a humbling experience.”

After receiving the news, Coleman immediately called his parents. He said that his mother was overjoyed given the time he put into the sport.

“She was extremely excited as I have been running track since I was 5 years old,” he said. “Everybody has really been supporting me. All my friends and family are back home watching and I am happy to be able to do this. They have been supporting me for a long time.”

The Olympics is the latest accomplishment for Coleman. In two seasons at Tennessee, he has won the 2016 Indoor 200 meters championship and been named a two-time All-American in the 100 and 200 meters.

Coleman also broke the nearly 14-year-old school record in the 100 meters, set by Gatlin. He beat the mark with a time of 10.03 seconds at the 2016 NCAA Championships. When Gatlin found out, he gave Coleman some advice to keep going.

“He was telling me to carry the Tennessee tradition as we have a great legacy of sprint guys,” he said. “Tennessee track and field flies under the radar, but we are gritty and we get down to it.”

But before he returns to Tennessee, the 20-year-old hopes to run one more time at the Rio Games. His teammate, Mike Rodgers, said there is a chance based on how good Coleman has been throughout the Olympics.

“I warmed up with him,” Rodgers said. “He was confident and he got the stick (baton) and made a great pass to Tyson (Gay). It was a safe pass that got through and tomorrow (Friday) it will be very exciting.”

Regardless of what happens, Coleman plans using his Olympic moment to further his collegiate track career.

“I am soaking it all in and hopefully continue to get better,” he said.