Serena Williams put up both hands after sending a forehand long and high over the baseline in the first set.
She wanted nothing to do with yet another unforced error in her Australian Open final against Angelique Kerber.
For the second time in as many majors, Williams fell short of equaling Steffi Graf's Open-era record of 22 Grand Slam singles titles.
No. 7-seeded Kerber had never played in a major final and had lost five of her six previous career meetings with Williams, but she responded with a stunning 6-4, 3-6, 6-4 upset win over the six-time Australian Open champion.
Williams had won the title every previous time she'd reached the final at Melbourne Park, and was overwhelming favorite to continue that streak against Kerber, who joked she was "one leg in the plane to Germany" when she faced match point in her first-round win over Misaki Doi.
"I mean, every time I walk in this room, everyone expects me to win every single match, every single day of my life," Williams said in her post-match news conference. "As much as I would like to be a robot, I'm not."
The 28-year-old Kerber used acute angles to keep Williams guessing, tossed in two drop shots for a crucial break in the long sixth game of the third set, and continually tried to pass the 21-time major winner or forced errors at the net.
And she had five service breaks - two in the first, and three in third set - against the top-ranked Williams, who hadn't dropped a set in the previous six rounds.
"My whole life I was working really hard and now I'm here and I can say I'm a Grand Slam champion," said Kerber, who had only reached the semifinals twice at the majors and hadn't been beyond the quarterfinals since Wimbledon in 2012.
"It sounds really crazy and unbelievable."
She is the first German woman to win the Australian title since Graf in 1994, and is projected to rise to No. 2 in the rankings next week.
German Chancellor Angela Merkel was quick to respond, saying "It was fascinating to see how courageously and with such nerves of steel how you prevailed against arguably the best player in the world."
And other congratulatory messages poured in.
"My phone is exploding right now," Kerber said. "It's so good also for German tennis.
After Steffi, now somebody won a Grand Slam.
"It took her 33 majors to win the title - sixth on the list for longest waits that is topped by 2015 U.S. Open champion Flavia Pennetta's 49.
Williams admitted previously she became nervous and was stalled for a while trying to get to 18 major titles, to equal Chris Evert and Martina Navratilova's career marks in second spot in the Open era. For three majors, Williams didn't reach the quarterfinals, but when she finally won her 18th, it triggered a roll of four straight major titles.
Now she's on 21.
"I was nervous before the match," Williams said. "Once it got started, it was so intense ... I didn't really have time to be nervous."
Williams won the Australian Open, French Open and Wimbledon titles last year before losing to Roberta Vinci in the U.S. Open semifinals.
After being so close to a calendar-year Grand Slam in 2015, she has no chance to push for that honor in 2016 after losing the season's first major.
Despite a rash of uncharacteristic unforced errors, Williams pushed Kerber all the way.
She had never lost a major final that went three sets, and she had only lost to three players - twice to her sister Venus (U.S. Open 2001, Wimbledon 2008), and once each to Maria Sharapova (Wimbledon 2004) and Sam Stosur (U.S. Open 2011) .
Kerber had a chance to serve for the match at 5-3 in the third but couldn't hold. Williams had a chance to level but dropped her serve, too. It finished when she hit a forehand volley long on championship point, her 46th unforced error.
Kerber dropped her racket on the court and lay flat on her back as Williams walked around the net to embrace her.
"She had an attitude that I think a lot of people can learn from - to always stay positive and never give up," Williams said.
"If I couldn't win, I'm happy she did."
Kerber credited Williams with being an inspiration to a generation of players."You created history, you are a champion, you are a really an unbelievably great person," Kerber said.
"So congratulations for everything you did already."Novak Djokovic is chasing history on Sunday night, aiming to join Roy Emerson as the only six-time Australian Open champion. He's 5-0 in finals at Melbourne Park, and will be meeting Andy Murray, who is 0-4 in finals here.
Murray was at Rod Laver Arena after midnight to see his older brother, Jamie, combine with Bruno Soares to beat Daniel Nestor and Radek Stepanek 2-6, 6-4, 7-5 for the men's doubles title."Andy, you should be in bed," the older sibling said.