Serena Williams was knocked out of the Miami Open in the first round by Naomi Osaka as the 23-time Grand Slam winner continues her return after pregnancy.
Williams, unseeded after taking 13 months off to have her first child, was beaten 6-3 6-2 by the Japanese, 20.
Her defeat comes after the Miami Open director said seeding rules for players coming back after maternity leave were a "punishment" and "should be changed".
Osaka is herself also unseeded but last week claimed victory at Indian Wells.
It was her maiden title and helped move her up to 22 in the world.