The One Direction heartthrob was pictured leaping to his feet at the SW19 courts on Thursday (26 June) while watching Nadal taking on Lukas Rosal.
Niall was looking really rather handsome in his smart black trousers and white shirt, wasn't he?
The Irish star was joined at the tennis by his bandmate Liam Payne, who was looking slightly less enthused than Niall in these pictures.
As well as watching the pros in action, Niall gave fans a treat by uploading a throwback picture to Instagram showing himself and Liam on the tennis courts together way back.
How insanely young do they look here?!
Niall and Liam were enjoying some time off from their mammoth 'Where We Are World Tour' which recently played Wembley Stadium. Not bad considering they only formed as a band FOUR YEARS AGO!
During his time at the tennis today, Niall met up with tennis star Caroline Wozniacki, who revealed herself to be a Directioner via Twitter thanks to a very excited tweet!
Caroline wrote: "Highlight of the day was to meet Niall and get a selfie taken with him! #excited."
Niall replied: "Nice to meet you."
Hopefully the singer was feeling a bit better today. He tweeted overnight that he'd injured his knee after fans at a recent concert threw things onstage. Which definitely isn't good considering he underwent major knee surgery in January. Poor Niall.
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