Vasek Pospisil was eliminated in the second round of the Miami Open tennis tournament in Key Biscayne, Fla., on Friday.
The Canadian took the opening set 7-6(1), but opponent Joao Sousa responded by winning the final two sets 7-6(5) and 6-2.
Milos Raonic faces American Denis Kudla on Saturday, while Eugenie Bouchard's slump continued with a first-round exit earlier this week.
Federer's return on hold
Roger Federer's return from knee surgery will have to wait after the Swiss maestro withdraw from his second-round match on Friday because of a stomach virus, tournament officials said.
Federer, sidelined for almost two months after tearing his meniscus, was due to play Argentine Juan Martin del Potro who defeated the former world number one in the 2009 U.S. Open final.
Lucky loser Horacio Zeballos of Argentina will replace the 17-times grand slam champion in the Miami Open draw.
The 34-year-old Federer said on Thursday that he had injured his knee in a freak domestic accident after slipping while running a bath for his twin daughters following his semi-final defeat at the Australian Open at the start of 2016.
Venus beaten by qualifier
In women's play, No. 10 Venus Williams lost her serve nine times and was beaten by qualifier Elena Vesnina 6-0, 6-7 (5), 6-2. It was the earliest exit ever for Williams in 17 appearances at Key Biscayne, but she took the loss well.
"I always enjoy my time on the court," she said. "I have a blast every single tournament, whether I win or lose."
Williams won the title in 1998, 1999 and 2001.