The reigning 100m world champion made his comeback in January after the 18-month suspension for failing to adhere to whereabouts requirements, which kept him from last summer's Tokyo Olympics.

On Sunday the 26-year-old finally hit the track in Japan's National Stadium for his first 100m this season -- an experience that left him feeling "pretty good" overall.

"I feel excited to have opened up my season with a pretty decent time... it's definitely something I can continue to build off," Coleman said after the race at the Golden Grand Prix 2022.

"This is my first 100 in a few years. So I put a lot of expectations on myself, and so I feel like I give myself a B+ overall."

Japan's Yuki Koike took second place in 10.22sec, and Australian Rohan Browning came third in 10.23sec.

The 100m season best is held by Kenya's Ferdinand Omanyala, who ran it in 9.85sec on Saturday in Nairobi.

Spectators were barred from Olympic athletics events over Covid-19 concerns, but on Sunday fans filled the stadium's lower stands, clapping enthusiastically for their favourites.

"To come here and compete in the Olympic Stadium is always exciting, and it's a blessing," said Coleman, who in March took silver in the 60m at the World Indoor Championships, losing out to his rival Lamont Marcell Jacobs.

American athletes dominated the main events on Sunday, including Rai Benjamin, who took silver in the 400m hurdles at last year's Olympics with a blistering time of 46.17sec.

On Sunday he came first in the same event, clocking in at 48.60sec.

"Time was slow, I'll say that much, but it felt really good to be back out there," he said.

And US runner Michael Norman won the men's 400m, but said he was not happy with his time of 44.62sec.

"I've been struggling since last year, it's been very apparent," he said.

"I've been having a hard time finding the race rhythm and setting up the race correctly... there needs to be a lot of improvement in the next couple of weeks."