MELBOURNE, Australia — Ashleigh Barty ended a 44-year wait on Saturday night, defeating Danielle Collins of the United States to become the first Australian player to win the Australian Open singles title since 1978.

Barty defeated Collins in straight sets, 6-3, 7-6 (2).

Barty, born and raised in the steamy Australian state of Queensland, has been ranked No. 1 for more than 100 weeks and has become a hugely popular figure in her home nation. Her matches during the Open this year have attracted large television audiences.

But until now, her most significant triumphs have come far from home. She won her first Grand Slam singles title in 2019 at the French Open and won Wimbledon last year when most Australians were unable to travel because of coronavirus restrictions.

But she was able to organize a “Barty Party” at home this year, defeating the 27th-seeded Collins in prime time in Melbourne.

Collins, 28, was a two-time N.C.A.A. singles champion at the University of Virginia and did not turn fully professional until she was 22, quite a contrast with Barty, who began her professional career at age 14.

Collins, an aggressive baseliner and fierce competitor, reached her first Grand Slam final by fighting her way through a series of matches in Melbourne, including three-set victories over Clara Tauson in the third round and Elise Mertens in the fourth round. Collins will rise to No. 10 in the world rankings after her run and become the top-ranked American for the first time.

But she could not stop Barty from ending a national drought. The last Australian to win the Australian Open in singles was Chris O’Neil, an unseeded player ranked outside the top 100 who never made another deep run at a major tournament after her victory in 1978.

Barty, 25, has now solidified her spot as the world’s top-ranked player and has won her three Grand Slam singles titles on three different surfaces, red clay at the French Open, grass at Wimbledon and hardcourt in Melbourne. The only Grand Slam singles title she has yet to win is the U.S. Open, although she did win the women’s doubles title in New York in 2018 with her American partner, CoCo Vandeweghe.

At 5-foot-5, Barty is not physically imposing in a sport increasingly populated by taller players like the 5-foot-10 Collins. But Barty is a complete threat, able to adjust her game on the fly and hit a particularly wide variety of shots. She can serve and drive her forehand with overwhelming power, but she can also opt for finesse, making frequent and devastating use of a technically sound single-handed slice backhand that skids low after the bounce and is difficult for many players to counter. Barty, as her doubles prowess makes clear, is also comfortable at the net and has some of the best volleys in the game as well as a spectacular overhead.

A prodigy, she took an indefinite break from the game at age 18 after the 2014 U.S. Open as she struggled to adjust to the travel and expectations that came with playing on tour. She played professional cricket before returning to tennis in February 2016, when she began working with Craig Tyzzer, a veteran Australian coach.

They have formed quite a partnership and have worked to develop Barty’s game while preserving her mental health and enthusiasm. She did not compete on tour for most of 2020 because of coronavirus restrictions, and after her successful summer in 2021, she chose to return to Australia after losing in the third round of the U.S. Open instead of remaining overseas and competing in the WTA Finals in Mexico.

Barty was weary and homesick after months on the road, and the decision to take a break has paid off at the start of 2022. She is 11-0, winning the title in Adelaide and now, most significantly, seven matches at the Australian Open.