Serena Williams celebrates winning her first-round match against Montenegro's Danka Kovinic at her final US Open on Monday. Reuters
Serena Williams celebrates winning her first-round match against Montenegro's Danka Kovinic at her final US Open on Monday. Reuters
Serena Williams hopes to 'run a billion-dollar fund' after tennis
American star's early-stage investments company Serena Ventures raised $111m earlier this year
