Angelique Kerber upset Serena Williams 6-4, 3-6, 6-4 to win the Australian Open title on Saturday, ending the six-time champion's unbeaten streak in finals here and winning a major title for the first time.

Williams was an overwhelming favourite at Melbourne Park, where she had won all six previous times she'd reached the final, and was trying to equal Steffi Graf's Open-era record of 22 Grand Slam singles titles.

For the second time in as many majors, though, she fell short. Williams won the Australian Open, French Open and Wimbledon titles last year before losing to Roberta Vinci in the U.S. Open semifinals.

She was so close to a calendar-year Grand Slam in 2015, but now has no chance to push for that honour in 2016 after losing the first major of the year.

The 34-year-old Williams hadn't lost a set in the first six rounds at Melbourne Park until dropping the first against No. 7-seeded Kerber, who was playing in her first major final.

Kerber had only ever beaten Williams once — in 2012 — in six career meetings, and was coming off a shaky start to the tournament when she had to save a match point in her first-round win over Misaki Doi.

She lost in the first round last year here and said again she was "one leg in the plane for Germany" against Doi. Now she's the first German woman to win the Australian title since Graf in 1994.

Despite a rash of uncharacteristic unforced errors, Williams made Kerber push all the way.

The 28-year-old Kerber had a chance to serve for the match at 5-3 in the third, but Williams broke back.

Williams couldn't hold in the next game, though, and hit a forehand volley long on championship point, her 46th unforced error of the match.

Kerber let her racket fly out of her hand and dropped on her back as the ball landed long. She got up to see Williams walking over to her side of the net, and the pair met at mid-court for a hug.

"Let me be the first to congratulate you," Williams said in her post-match speech. "Enjoy the moment. I'm so happy for you."

Told later that she appeared to be as happy about the result as Kerber was, Williams said: "Really, I should get into acting!"

But, she added, "I was really happy for her. She's been around a long time. She had an attitude that I think a lot of people can learn from — to always stay positive and never give up.

"If I couldn't win, I'm happy she did."

Kerber had cried as she walked over to her support team, then back to the centre of the court with one arm raised.

At the ceremony, she was all smiles again.

"You are really an inspiration for so many people, so many young tennis players," Kerber said, paying tribute to Williams in her victory speech. "You created history, you are a champion, you are a really an unbelievably great person, so congratulations for everything you did already."

Kerber's previous best performances at a major were semifinal exits at the U.S. Open in 2011 and Wimbledon in 2012. She had only reached the quarterfinals once in the 13 majors leading into 2016.

"My whole life I was working really hard and now I'm here and I can say I'm a Grand Slam champion," she said. "It sounds really crazy and unbelievable."