Australian Open Day 1: Naomi Osaka, Rafael Nadal speed into second round

The Australian Open is underway notably without men's No. 1 player Novak Djokovic, who was deported after an appeal to have his visa reinstated was shot down. Now the attention turns to the tennis action and on Day 1 there were a handful of upsets on the women's side, including to the two highest-ranking Americans.

Osaka, Nadal advance in returns

Naomi Osaka moved into the next round with a 6-3, 6-3 win over Camila Osorio. She won the first five games of the match as she looks to defend her Australian Open crown. The four-time Grand Slam singles champion also won in 2019.

Osaka, 24, showed off a bit of a superstition in the opening match by avoiding stepping on the "Melbourne" signage on the court. She had 19 winners to Osorio's five and an 83% win percentage on the first serve. Osaka is seeded 13th after sliding in the rankings while taking time off last year. She withdrew from the French Open and skipped Wimbledon before early exits at the Tokyo Olympics and U.S. Open.

Osaka will face American Madison Brengle in the second round.

Rafael Nadal, seeded sixth in the men's draw, also advanced in straight sets, 6-1, 6-4, 6-2 against Marcos Giron. Nadal missed the end of the 2021 season with a foot injury. He won the Summer Set title in Melborne two weeks ago, his first tournament win in Australia since the Australian Open in 2009.

Nadal, 35, is tied with Djokovic and Roger Federer for most major singles titles in men's tennis history. Each player has 20 and Nadal is the only one of them in the draw. Djokovic did not meet the country's strict COVID-19 vaccination criteria that created an 11-day saga. Federer is currently injured.

Nadal will face Yannick Hanfmann, who won in straight sets, in the second round.

Women's draw: Top seeds advance

Ash Barty, the No. 1 ranked player on the women's side, had little trouble advancing through with a 6-0, 6-1 victory over Lesia Tsurenko. Barty will face Lucia Bronzetti of Italy next.

It took Barty only 54 minutes to get through as the Australian seeks her first Australian Open title. She faced game points in only the third game and saved them with a forehand winner and ace.

No. 4 seed Barbora Krejcikova also won with ease, 6-2, 6-0, over Andrea Petkovic. No. 5 seed Maria Sakkari played a closer match, escaping with a 6-4, 7-6 (2). It's her first time seeded 10th or better in a Grand Slam in her career.

Coco Gauff, Sofia Kenin head home early

Coco Gauff and Sofia Kenin are taking early trips home after upsets in the first round in Melbourne.

Gauff, seeded 18th, is the only player in the WTA top 200 younger than 18. The teenage sensation lost to Chinese player Wang Qiang 6-4, 6-2. Gauff had 38 unforced errors and 15 winners. It's the first opening round defeat for the American star since the 2020 U.S. Open.

Kenin, who won the tournament in 2020, lost to American veteran Madison Keys 7-6 (2), 7-5. Kenin was seeded 11th and Keys is coming off a title win at Adelaide. It was Keys' first WTA title in two years.

Men's draw: American scores upset

American Sebastian Korda pulled off the biggest upset of the men's draw on the first day. He took down No. 12 seeded Australian Cameron Norrie, 6-3, 6-0, 6-4.

Korda will face Frenchman Corentin Moutet in the second round. Moutet dropped the first set of the tournament, but bounced back to win the next three against fellow countryman Lucas Pouille.

Alexander Zverev, seeded third, won 7-6 (3), 6-1, 7-6 (1) against Daniel Altmaier. He was the only top-five men's player to hit the court on the Grand Slam's first day.