“Playing first rounds in grand slams are always tough, especially with my first-round match that I lost in Paris,” said Kerber, who had more unforced errors than winners. “I was actually just thinking about point-by-point, trying to finding my rhythm during the whole match.”

“There’s got to be a rule for guys who come out clearly not giving or able to give 100 percent,” said BBC commentator John McEnroe on the two straight retirements stunning fans on center court. “It’s no good for anyone.”