Roger Federer has hired Paul Annacone as a full-time coach after a successful trial period over the past month.

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Federer looked rejuvenated on the North American hard court circuit with Annacone in tow, successfully defending his Cincinnati title and reaching the Toronto final.

Annacone's current contract with the UK Lawn Tennis Association runs out in November and from then on he will be full-time with Federer with Swiss Davis Cup coach Severin Luthi also helping out as an advisor.

"It's just nice to hear a fresh, different voice for a change," Federer said. "I just think the dynamics work really well with Severin, and Paul and me coming into the conversation just makes it really interesting. I can go with a very clear mindset into the matches."

Annacone will be with Federer throughout the US Open as the Swiss bids to win his sixth title at Flushing Meadows. He has reached the final every year since 2004.

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