Casper Ruud survives first-round Australian Open scare, thanks famous dad in wholesome interview

Sixth seed Casper Ruud avoided becoming the victim of the first major upset of this year's Australian Open as he saw off a spirited Spaniard in five sets on Sunday.

Many expected the Norwegian to breeze through world No.61 Jaume Munar, a training buddy of his at the Rafa Nadal Academy in Mallorca, but every Ruud surge was met with a Munar fightback.

On a rain-drenched opening day marred by a slew of delays and eight cancelled matches, Ruud prevailed indoors in a 6-3, 1-6, 7-5, 2-6, 6-1 win.

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The 26-year-old's high-profile father, former tennis professional Christian Ruud, was courtside at Rod Laver Arena as his son's coach.

And it was pointed out during Casper's on-court interview after the five-set clash that he had never advanced further at an Australian Open than his dad, prompting a cheeky dig.

"Yes, it is, for sure," he said when asked if they had a father-son rivalry.

"But I have a better record in most of the other tournaments, so this is kind of the last one standing for him. I hope I can beat it one day, but I'm happy if he also has one record at least in the family."

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The furthest Christian advanced at an Australian Open was the fourth round, which he reached in 1997; the deepest Casper has gone at Melbourne Park is also the fourth round, in which he featured in 2021.

Casper, a former world No.2, has contested three grand slam finals — two at Roland-Garros and one at the US Open.

He had wholesome words for his dad, who watched on with a warm smile during his son's on-court interview.

"He has inspired me a lot and I think without him it would be very difficult to get where I am today, so I owe him a lot and I have to thank him a lot because he always helped me along the way," Casper said.

"I'm really happy with the work that we've done."

Ruud said his clash with Munar was "really tough".

"I know Jaume well because we are both practising a lot in the Rafa Nadal Academy in Mallorca," Ruud said.

"... When you know someone quite well it's also tricky because he knows my game, I know his game, and we are good friends also, so it can be a bit difficult.

"I told him at the net I got a bit lucky in the end.

"I'm happy I stepped up and played some good points when I had to."

Ruud will face the winner of the match between Georgia's Nikoloz Basilashvili and Czezh Jakub Mensik in the second round.