![TENNIS on Twitter: "Nicolas Kiefer shares an epic #ThrowbackThursday photo of a very young, long-haired Federer, Haas and more: https://t.co/SmCb7RuuBI https://t.co/35jIpPBxHt" / Twitter TENNIS on Twitter: "Nicolas Kiefer shares an epic #ThrowbackThursday photo of a very young, long-haired Federer, Haas and more: https://t.co/SmCb7RuuBI https://t.co/35jIpPBxHt" / Twitter](https://pbs.twimg.com/media/DgPToHxUcAE-MV1.jpg:large)
TENNIS on Twitter: "Nicolas Kiefer shares an epic #ThrowbackThursday photo of a very young, long-haired Federer, Haas and more: https://t.co/SmCb7RuuBI https://t.co/35jIpPBxHt" / Twitter
![Roger Federer: Novak Djokovic and Wimbledon warning fired at star by Nicolas Kiefer | Tennis | Sport | Express.co.uk Roger Federer: Novak Djokovic and Wimbledon warning fired at star by Nicolas Kiefer | Tennis | Sport | Express.co.uk](https://cdn.images.express.co.uk/img/dynamic/72/590x/Roger-Federer-Novak-Djokovic-and-Wimbledon-warning-fired-at-star-by-Nicolas-Kiefer-1095560.jpg?r=1551745854559)
Roger Federer: Novak Djokovic and Wimbledon warning fired at star by Nicolas Kiefer | Tennis | Sport | Express.co.uk
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