It's not clear if the Canadian's relationship with current coach Thomas Hogstedt has changed.
The 2014 US Open champion pulls out with a knee injury.
Slovakia's Dominika Cibulkova made her feelings on Maria Sharapova quite clear.
Roberta Vinci climbs to a new career-high ranking, while Victoria Azarenka climbs to the top of the Singapore standings.
Nick Kyrgios became the top-ranked Aussie for the first time as a result of his semifinal performance in Miami.
"To be brave and take risk is the way you're going to win," world No. 4 says.
Tennis timber: Australian Open announces wood replaces hard court for 2017.