Iga Swiatek made light work of Emma Raducanu, beating her 6-1, 6-0 to progress to the Round of 16.
World No. 2 Iga Swiatek will face a tricky third round tie against Britain's Emma Raducanu.
Roared on by Brazilian fans decked out in yellow, Joao Fonseca appeared totally unfazed as he set up a second-round meeting with Italy's Lorenzo Sonego.
Jannik Sinner and Iga Swiatek have both faced doping investigations.
Great Britain's Emma Raducanu is travelling with renowned fitness coach Yutaka Nakamura in an attempt to better withstand the rigours of professional tennis.
Raducanu was scheduled to play with former Wimbledon champion Murray on Saturday, but opted to pull out of the tie due to a stiff wrist.
Carlos Alcaraz is chasing a fourth Grand Slam title and attempting to become just the sixth man to win the French Open and Wimbledon back-to-back.
The men's doubles loss is not the final game of Murray's career, as he is set to participate in the Wimbledon mixed doubles alongside fellow Brit Emma Raducanu.
The two-time Wimbledon singles champion will also play men's doubles with his brother Jamie at the All England Club.
Emma Raducanu has declined the opportunity to represent Great Britain in next month's Paris Olympics.