Two 21-year-olds faced off on Rod Laver Arena to kick off Day 3 at the 2023 Australian Open, and it was World No.1 Iga Swiatek who prevailed under the closed roof by defeating 84th-ranked Camila Osorio 6-2, 6-3 in 1 hour and 24 minutes.

More from Day 3:

"It was really intense, and pretty physical," Swiatek said in press, after her win. "I think it was much tougher than what the score says."

Here are some takeaways from the top seed’s latest victory on a rainy Wednesday:

Swiatek's power game pays off: Both Swiatek and Osorio had starry junior careers at around the same time. The year after Swiatek won 2018 Junior Wimbledon, Osorio captured the 2019 Junior US Open and ascended to Junior World No.1.

Osorio has already tasted success on the Hologic WTA Tour, winning her first title on home soil in Bogota two years ago, and making two additional finals since. She reached a career-high ranking of World No.33 in April of last year.

On Wednesday, Osorio’s abilities to hyperextend rallies and change the direction of the ball down the line at a moment’s notice allowed her to hang with the World No.1 in a number of close games. Osorio even broke Swiatek three times, including when the Pole served for the match at 6-2, 5-1.

But in the end, the Swiatek power game which has led her to the top of the rankings was the determining factor. Swiatek used her forehand to great effect, with 13 rally winners from that side.

Swiatek also won 64 percent of points returning Osorio's first serve -- an even better success rate than when she returned the Osorio second serve (57 percent of points won).

"I know [Osorio is] gonna fight till the end and she's not going to give anything for free," Swiatek said. "She made some good decisions as well. I'm pretty happy that I was solid, and that's the most important thing for me."

Swiatek continues to dominate early: The Polish star has also become unshakeable in early rounds of Grand Slams, fortifying her rise to the top. This continued on Wednesday, when she won her 12th straight second-round match at a major. Swiatek hasn't lost before the third round of a major since the 2019 US Open.

Swiatek has now won 53 of her first 65 main-draw Grand Slam singles matches. In the Open Era, only six players had more such wins after their first 65 matches in majors: Margaret Court (61), Monica Seles (60), Chris Evert (57), Martina Hingis (56), Billie Jean King (56) and Tracy Austin (54).

Surprises ahead for the World No.1: Swiatek could have faced a fellow Grand Slam champion in her next match, but instead, she will meet a qualifier in the third round.

Cristina Bucsa, who made her Top 100 debut this very week at World No.100, upset 2019 US Open champion Bianca Andreescu to reach the third round of a major for the first time in her career.

Round 1 Day 3 highlights: Vekic d. Selekhmeteva | Potapova d. Stephens | Stefanini d. Maria | Siegemund d. Bronzetti | Gracheva d. Kasatkina | Vondrousova d. Riske-Amritraj | Parrizas Diaz d. Haddad Maia

Rising 25-year-old Bucsa knew exactly what she had set up with her big win: she immediately mentioned Swiatek without even being prompted in her on-court interview after beating Andreescu.

"A very big challenge for myself," Bucsa said, when asked to expand further on her upcoming meeting with Swiatek. "I'm going to do all my best, and I hope to see [this crowd] in the next round."

Round 2 Day 3 highlights: Sakkari d. Shnaider | Pegula d. Sasnovich | Kalinina d. Kvitova | Zhu d. Teichmann | Baindl d. McNally | Ostapenko d. Bondar | Bucsa d. Andreescu | Gauff d. Raducanu | Collins d. Muchova

Swiatek has faced Bucsa once before: at a junior event in Umag, Croatia, in 2016. Swiatek won that match 6-4, 4-6, 6-0.