Serena Williams started her final slam appearance with a victory against Danka Kovinic, beating the Montenegrin in two sets of 6-3, 6-3 in one hour and 39 minutes.
By winning, Williams extended her carrier by at least one more singles match, as she announced her retirement from the sport earlier in August.
In her next US Open encounter, Williams will clash with second-seeded Anett Kontaveit of Estonia.