It was debut tournament as a team for Mektic and Krajcikova, up against an experienced duo with multiple Grand Slam titles. Mattek-Sands was bidding for her 10th Grand Slam doubles title and Murray, the older brother of Andy, was chasing his eighth major crown.
Sofia Kenin of the United States has beaten Garbiñe Muguruza of Spain to win the Australian Open for her first Grand Slam title.
The 21-year-old Kenin won by a score of 4-6, 6-2, 6-2 with the retractable roof at Rod Laver Arena closed because of rain.
Kenin was seeded 14th.
She had never been past the fourth round of a major tournament until now.
Kenin reached the first Grand Slam final of her career by beating No. 1 Ash Barty in the semifinals.
Muguruza is a former No. 1-ranked player who won the French Open in 2016 and Wimbledon in 2017.
The Australian Open women's final is going to a third set.
Sofia Kenin won the second set 6-2 to level the match after Garbiñe Muguruza took the first set 6-4. The 14th-seeded Kenin is playing in the final of a major for the first time. Muguruza has won Grand Slam titles at Wimbledon and the French Open.
The women's final is being played under a closed roof at Rod Laver Arena after a rainy day in Melbourne.
Garbiñe Muguruza has taken the first set 6-4 in the Australian Open final against 14th-seeded Sofia Kenin.
Muguruza, a two-time major winner, converted two of her nine break-point chances — in the third and ninth games. Kenin converted the first break point opportunity she got in the eighth game. The 21-year-old American is playing in her first major final.
The Australian Open final between two-time major winner Garbiñe Muguruza and 14th-seeded Sofia Kenin has started under a closed roof on Rod Laver Arena following a cool, rainy afternoon in Melbourne.
Former No. 1-ranked Muguruza is unseeded at the tournament but has won majors at the French Open and Wimbledon and is aiming for her first Grand Slam title on a hard court.
The 21-year-old Kenin is into a major final for the first time and was serving first. Until her breakthrough run at Melbourne Park, she'd never gone past the fourth round at a Grand Slam tournament. She beat top-ranked Ash Barty in the semifinals to ensure Australia's long title drought at the season's first major continued.
The junior women's champion at the Australian Open admits she has split nationalities — Andorra and Spain. But her allegiance is firmly with Andorra, one of the smallest states in Europe.
Victoria Jimenez Kasintseva came from a set down to beat Weronika Baszak of Poland 5-7, 6-2, 6-2 in the final at Melbourne Park.
The 14-year-old Kasintseva said she picked up her first racket at the age of 3 and began playing on court with her dad, who has a small tennis academy, at the age of six.
She said she frequently travels between Andorra and Spain, where the academy is located.
Andorra is a small independent European principality situated among the southern peaks of the Pyrenees Mountains and bounded by France to the north and east and by Spain to the south and west.
"I only represent Andorra. Yeah, I live in between them two," she said.
In the meantime she will return to her school studies while juggling her promising tennis career.
"Well, I'm going to do preseason now, like one month of studying, a lot of physical preparation," she said. "Obviously I'm going to try to improve my shots. Then I'm going to play my first tournament, it's a 15K ($15,000 tournament) in March, I think in France."
Victoria Jimenez Kasintseva of Andorra came from a set down to beat Weronika Baszak of Poland 5-7, 6-2, 6-2 in the junior women's final at Melbourne Park. Harold Mayot beat Arthur Cazaux 6-4, 6-1 in the all-French boys' final.
The women's final between two-time Grand Slam champion Garbiñe Muguruza and 21-year-old American Sofia Kenin was scheduled for the first night match at Rod Laver Arena.
The mixed doubles final was to follow. Britain's Jamie Murray and American Bethanie Mattek-Sands were to play fifth-seeded Barbora Krejcikova of Czech Republic and Croatia's Nikola Mektic. Mattek-Sands already has five women's doubles titles and four in mixed, while Murray is going for his eighth doubles title overall.
More AP Tennis: https://apnews.com/apf-Tennis and https://twitter.com/AP_Sports