Daniell/Venus were making their second appearance at the Olympics this week
Daniell and Venus, who also teamed at the 2016 Rio de Janeiro Olympics, saved all three break points they faced. They won 75 per cent (33/44) of their first-service points to claim victory in one hour and 49 minutes.
Venus has won two tour-level titles this year at the Hamburg European Open (w/Puetz) and the Gonet Geneva Open (w/Peers), while Daniell enjoyed a run to the final at The Qatar ExxonMobil Open (w/Oswald) in March.
Krajicek and Sandgren were making their Olympic debuts this week and were teaming for the fifth time this year.