Annabel Croft reveals what is most worrying about Federer after Nishikori ATP finals defeat

Roger Federer is starting to show the “yips” that he never previously showed, according to the Sky Sports pundit Annabel Croft. “Underneath the surfaces are these nerves and jitters,” Croft said. “When he's going out there, there are a little bit of the yips coming into play and we're just not used to seeing it. He's not free-flowing. He's stuttering and thinking more, even on the basic groundstrokes.”

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