Serena Williams' coach has revealed that the world number one may skip the remaining matches of the year, as she is still struggling to overcome her US Open loss.
Earlier this month, Roberta Vinci had crushed Serena's hopes of completing a calendar grand slam by claiming a 2-6, 6-4, 6-4 win at the Flushing Meadows.
Reflecting on her semi-final loss, coach Patrick Mouratoglou insisted that Serena's strategy was not wrong, but added that she did not come with the right mindset on that day, the Guardian reports.
Mouratoglou also said that the American considers her 2015 season as 'not good' after losing the US Open semi-final, pointing that Serena showed signs of a true champion for keeping high expectation from herself.
He also insisted that Serena should not prefer to play if she lacks motivation to play in the upcoming tournaments.
The 21-time Grand Slam champion is scheduled to play in next month's China Open and the WTA Finals in Singapore.
Serena won three Grand Slams this season -- the Australian Open, the French Open and Wimbledon.