Tennis champ Andy Murray says changing nappies is his biggest challenge yet.

He might be the second best tennis player in the world – but for Andy Murray, fatherhood (and nappy changing) are proving to be his toughest challenge yet.

The 28-year-old married childhood sweetheart Kim Sears last year, and the couple welcomed baby Sophia last month.

Now, The Daily Mail reports that Murray has opened up about fatherhood for the first time.

"The thing that has surprised me most is how quickly everything changes – from the first day she was born," he said.

"You don’t notice it when you’re there every day but you look back at a photo on the day she was born to one taken five days later to now, a few weeks on, and you see how much things change on a daily basis."

He told the Guardian he wanted to be there for his little family.

"I really don’t want to miss seeing those changes. Even when I’m away for a day I feel bad. I feel I should be there and I want to be there as much as I can," he said.

"So when I’m leaving the house at eight in the morning and getting back at eight at night, I feel bad."

New parents Kim Sears and Andy Murray. Images via Getty.

He also explained that nappy changing was his biggest challenge yet, because: "You see a small person and you think they're so fragile."

However, Scottish-born Murray said he was becoming more confident with each day.

He said he wanted Sophia to be "proud of her dad" when she grows up.

Congrats on your new arrival, Andy and Kim - we're sure you're great parents already.

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