As usual, Naomi Osaka’s postmatch interview struck an emotional chord.

It was two years after she had burst to the fore with a moving win over Serena Williams in the 2018 U.S. Open women’s singles final, where she had stood small and unguarded, crying in front of an audience that had been rooting for her opponent.

Now, in September, after winning the U.S. Open for a second time, the Japanese star was asked by the ESPN analyst Tom Rinaldi to explain why she had entered each of her seven matches wearing a face mask bearing the name of a Black victim of racist violence.