Caroline Wozniacki has given her doubters fresh ammunition by crashing out of the WTA tennis champioships in Istanbul, less than 24 hours after being crowned end-of-year world No.1.
The 21-year-old Dane is one of only seven women to finish consecutive seasons in the top spot, but her straight sets loss to Wimbledon champion Petra Kvitova has taken some of the gloss off her achievement.
Wozniacki's lack of a grand slam title, or a WTA Championship title, has undermined the legitimacy of her No.1 status.
Wozniacki has one of the fullest schedules among the top women - only one player in the top 10 has played more tournaments this year.
This has allowed her to keep on accumulating points as other players either skip events or miss them through injury.
The absence of Serena Williams and Kim Clijsters through injury for large chunks of the year has also aided Wozniacki's cause.