Kid’s night: Osaka, 20, beats her idol Serena to win US Open

Naomi Osaka, of Japan, holds the trophy after defeating Serena Williams in the women's final of the U.S. Open tennis tournament, Saturday, Sept. 8, 2018, in New York. (AP Photo/Adam Hunger)

NEW YORK — Naomi Osaka walked to the net, the excitement of being a Grand Slam champion mixed with a bit of sadness.