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Reigning Australian Open women’s champion Naomi Osaka said she’s been keeping a journal to document how she’s been feeling before defending her title.

The 25-year-old couldn’t have hoped for a better script for any potential entry she pens for January 17 as she won her opening match 6-3 6-3 against Colombian Camila Osorio on Rod Laver Arena.

Osaka, who is the 13th seed in this year’s draw, raced into a 5-0 lead in the opening set on Monday before some spirited play from 20-year-old Osorio and a few unforced errors allowed her a route into the match.

The Japanese star did eventually manage to clinch the first set. In the second set, Osorio had two early break points but was unable to take advantage.

Osaka broke into a 3-1 lead and a stray Osorio backhand into the net finally gave Osaka the victory to get her title defense off to the perfect start.

“I thought I played pretty well given the circumstances, I didn’t have a lot of information about my opponent,” said Osaka in her on-court interview.

She added: “I hope that we gave you a really good performance. It always feels very special for me to come back here. I have a lot of really good memories here.”

Osaka plays a forehand against Osorio during their women's singles match on day one of the Australian Open.

Osaka will face Madison Brengle in the second round after the American advanced when Dayana Yastremska retired trailing 1-6 6-0 0-5.

Earlier this month Osaka played her first match in four months after she took a break from tennis after a defeat to Leylah Fernandez at the US Open Last year, she also withdrew from the French Open, citing mental health issues, and chose not to participate at Wimbledon.

The four-time grand slam champion said she is prioritizing her enjoyment on the court during her time in Melbourne.

“I can’t expect myself to win every match, but I do expect myself to have fun and challenge myself,” she said. “I’m here because I want to be here and because I find that it’s fun for me.

“I accept the fact that I’ll have dips, and I need to figure out a way to overcome it.”

Osaka celebrates her match point against Osorio.

Could this be the year?

Like Osaka, Rafael Nadal’s Australian Open couldn’t have started any better as the Spaniard embarks on his bid to win what would be a record-breaking 21st grand slam victory,

The Spaniard beat Marcos Giron 6-1 6-4 6-2 in just one hour, 49 minutes to advance to the second round in Melbourne.

In what was his 70th win at the competition, Nadal continued his fast start to 2022 on the Rod Laver Arena.

Having missed the end of the 2021 season thanks to a foot injury, Nadal won the Melbourne Summer Set title two weeks ago, his first tournament win on Australian soil since the Australian Open in 2009.

And the 35-year-old maintained his good form against Giron, a dominant 24-minute first set setting the tone.

Nadal continued to keep his foot down throughout, breezing past world No. 66 Giron without too much fuss.

Nadal is the only former champion left in the draw – with Novak Djokovic deported and Roger Federer injured – meaning he can become the men’s all-time grand slam record winner by winning in Melbourne.

And he stressed the importance of winning last week at the Melbourne Summer Set after beating Giron.

“Last week had been important for me. I played three matches, I won three matches. I won a title, it’s always beautiful,” Nadal said.

“And I think I am doing better and better. You never know what’s going on, but I’m happy if you tell me I’m going to be in this position one month ago, of course without a doubt I would sign the paper (smiling).

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Nadal celebrates after winning against Giron.

“At the beginning (of a comeback), things are going to be difficult, of course you will not have the best feelings sometimes on court.

“But staying positive, playing with the right energy, and of course being on the tour practicing with the guys, and winning matches, for sure helps.”

Sixth seed Nadal will now face the winner of the match between wildcard Thanasi Kokkinakis and qualifier Yannick Hanfmann in the second round.