Kiwi doubles players Michael Venus and Marcus Daniell have copped a difficult draw at the Olympics.

They've been pitted against Canadian pair Daniel Nestor and Vasek Pospisil,with respective world rankings of ninth and 17th.

43-year-old Nestor has claimed 90 titles with 11 different partners including eight grand slam crowns and won Olympic gold in Sydney 2000.

Pospisil has won the Wimbledon doubles title.