Whybourn made the most of her wildcard entry by beating number-three seed Kai-Lin Zhang of China 2-6 6-3 7-5 on Monday after a two-hour battle, during which she saved two match points.
The 25-year-old, who will face Spain’s Georgina Garcia-Perez in the second round, has made a strong comeback from injury this year and earlier this month won the women’s doubles title with Australia’s Pia Konig at the $10,000 Santa Margherita Di Pula in Italy on clay.
Smith and Jocelyn Rae, who are Great Britain’s Federation Cup pairing, reached the second round at Roland Garros for the first time after battling back superbly to beat Japan’s Miyu Kato and Kurumi Nara 4-6 7-6(5) 6-3.
They then put up a good fight against number-three seeds Hao-Ching Chan and Yung-Jan Chan of Taiwan before going down 6-3 6-2.
New Zealander Daniell – coached by Dave Sammel, Ian MacDonald and Bob Smith at the University of Bath – went one better than Smith and Rae by reaching the third round of the men’s doubles with American Brian Baker.
They started strongly with a convincing 6-3 6-2 win over former Australian Open finalist Marcus Baghdatis of Cyrpus and Dmitry Tursonov of Russia.
Daniell and Baker then overcame Henri Kontinen of Finland and Australia’s John Peers 6-3 6-4 before their run was ended in the last 16 by a 6-2 6-7(4) 6-1 defeat to India’s Rohan Bopanna and Romania’s Florin Mergea.