"Everybody was saying I'm done, I'm through, I'm finished, I'm washed up," Greene said. "But who cares. No matter what the headlines say, you have to go to the line and be ready to run. This is the start of my year."
Only Australian Patrick Johnson has run faster this year, clocking 9.93 seconds last month in Japan. American Tim Montgomery holds the world record of 9.78 seconds, which he set last year.
J.J. Johnson placed second in 10.05 seconds, with Shawn Crawford third in 10.10.
Greene had predicted last month he would defend his world 100 metres title and win back the 200 metres crown at August's world championships in Paris.
But a sub-par showing of 10.33 seconds in a third-place finish at Portland two weeks ago cast doubts about his fitness.
Mexico's Ana Guevara, unbeaten over 400 metres since 2001, continued her impressive running by winning her event in 49.62 seconds.
American Kelli White clocked a wind-assisted 10.79 seconds in the women's 100 metres and 1996 Olympic champion Allen Johnson showed he had recovered from a calf injury by winning the 110 metres hurdles in a wind-assisted 13.20 seconds.
