MELBOURNE — Serena Williams gave another reminder of her dominance in women’s tennis with a 6-0, 6-4 win Thursday morning in the Australian Open semifinals against Agnieszka Radwanska, who is soon to move to the No. 3 ranking.

Six-time champion Williams has never lost a semifinal or final at the Australian Open.

The first set was no contest, over in 20 minutes. Williams hit 18 winners and Radwanska, in her fifth major semifinal, had one — in the fourth game.

The second set was closer, with Radwanska holding serve three times and breaking Serena’s powerful serve once. But the 34-year-old Williams lifted again to finish it off, winning the last eight points of the match and closing with three aces and a big forehand winner.

Despite her 21 major titles and all her success, it is a loss that is inspiring Williams in this tournament. She was two wins away from a calendar-year Grand Slam in 2015 when she lost to Roberta Vinci in the US Open semifinals.

‘‘Physically I'm feeling a lot better, mentally I needed that break after the Open,’’ she said, but ‘‘I didn’t think I would do this well this fast.

‘‘I'm really excited to be in the final — it just kind of blows my mind right now.’’

Williams remains unbeaten in nine matches against Radwanska, and is an overwhelming favorite going into the final against the winner of Thursday’s later match between No. 7-seeded Angelique Kerber and No. 47-ranked Johanna Konta, the first British woman since 1983 to reach a major semifinal.

With the roof on Rod Laver Arena closed because of a thunderstorm closing in, the most obvious noise in the first set was the chirping of trapped birds who'd taken shelter in the stadium.

The chirping intensified as Williams served in the sixth game of the second set, and she looked up angrily after her off-balance forehand from the baseline conceded her only service break of the match.

Williams finished with eight aces for the match — after none in the first set — and has dropped only 26 games in six rounds in a dominating run that included a 6-4, 6-1 win over No. 5 Maria Sharapova in the quarterfinals, a rematch of the 2015 final.

On Wednesday night, Andy Murray defeated David Ferrer, 6-3, 6-7 (5-7), 6-2, 6-3, to reach the semifinals at a Grand Slam for the 18th time. The 24-year-old Konta had a 6-4, 6-1 win over Chinese qualifier Zhang Shuai in the women’s quarters.

It’s the first time since the Australian Open in December 1977 that two British players (John Lloyd and Sue Barker) have advanced to the final four in the same major.

Konta is playing in her first Australian Open main draw, after losing in qualifying rounds three years in a row. She had a first-round win over No. 8 Venus Williams and beat Ekaterina Makarova in straight sets in the fourth round.

She has won fans at Melbourne Park with her athleticism and mental composure on the court and good humor and humility in interviews after winning. Born in Australia but living in Britain since her early teens, Konta also has Hungarian citizenship and calls herself a ‘‘tri-citizen.’’

Asked about her parents’ reaction back home in Britain, Konta apologized for making them stay up so late.

‘‘I’m pretty sure they have jet lag because of the time difference,’’ said Konta. “They’ve been staying up all ridiculous times of the morning.’’

Murray is impressed.

‘‘She’s done incredible,’’ he said. ‘‘Another very comfortable and solid win today. Not easy, either. She created that chance by beating the seeds, and she deserves to be where she is.’’

Konta is the first British woman to reach a Grand Slam semifinal since Jo Durie at the 1983 US Open. Konta’s semifinal opponent, Kerber, beat two-time champion Victoria Azarenka, 6-3, 7-5, n the quarterfinals.

The No. 2-ranked Murray, who has lost four finals at Melbourne Park, will meet Milos Raonic in the semifinals. The 25-year-old Canadian beat Gael Monfils, 6-3, 3-6, 6-3, 6-4, in a night match, continuing the strong form that saw him beat Roger Federer in the Brisbane International final and French Open champion Stan Wawrinka in the fourth round here.

Defending champion Novak Djokovic and Federer will contest the other men’s semifinal.

Murray and Raonic, who advanced to his second Grand Slam semifinal after losing to Federer in the final four at Wimbledon in 2014, are 3-3 in career meetings.

‘‘I think just the perseverance throughout it, I had a lot of opportunities even in that set I lost,’’ Raonic said of his win over Monfils. ‘‘I just said to myself, ‘Keep making opportunities and hopefully they’ll go my way.’ ’’