Serena Williams sounded a warning for her fellow Australian Open contenders with a sleek win
It was Novak Djokovic's first match this year after his Australian Open hopes were dashed when he was deported following an 11-day saga revolving around his decision not to have a COVID-19 vaccination.
Twice Shanghai Masters champion Roger Federer was far from his best against Spain's Roberto Bautista Agut but did enough to reach the quarter-finals with a 6-3, 2-6, 6-4 win on Thursday.
Former world number one Andy Murray won his first ATP tour singles match in nearly nine months with a 6-3, 6-7(6), 6-1 victory over American Tennys Sandgren in the opening round of the Zhuhai Championships.
The 25-year-old Dzumhur recovered from a poor start to beat the Briton 1-6, 7-5, 6-3 and will bid to become the Balkan nation's first Tour winner in Saturday's title-decider against Spain's Roberto Bautista Agut.
Williams had little trouble against the 31-year-old German although the gusty breezes at Auckland Tennis Centre played havoc with her ball toss, especially when she was serving for the match at 5-3 in the second set.
World number one Naomi Osaka was beaten in her opening match at the Dubai Duty Free Tennis Championships on Tuesday, losing to France's Kristina Mladenovic 6-3, 6-3 on her return to competitive action after winning last month's Australian Open.
Summary of sports events and persons who made news on Wednesday
American teenager Amanda Anisimova, fresh off an impressive run at Indian Wells, beat China's Wang Qiang 6-3, 1-6, 6-2 at the Miami Open on Tuesday to set up a second round clash with Spanish third seed Garbine Muguruza.
Former champion Stan Wawrinka battled past Russian fourth seed Daniil Medvedev in five sets to reach the Australian Open quarter-finals with a 6-2, 2-6, 4-6, 7-6(2), 6-2 victory. Fifth seed Dominic Thiem kept his flawless record against Gael Monfils intact with a trouble-free 6-2, 6-4, 6-4 victory on Monday to reach his maiden Australian Open quarter-final.
Djokovic, the ninth seed, was originally scheduled to play Australian Open semi-finalist Chung Hyeon but the 22-year-old South Korean withdrew with a back injury about an hour before the match was due to start.
Summary of sports events and persons who made news on Monday
A round-up of tennis matches played on Tuesday.
Images from Day 2 of the 2020 US Open in New York
Former US Open champion Del Potro fired down 11 aces and did not face a break point during the one hour, 33 minutes match.
Halep through but Stephens exits in Cincinnati
Greek tyro Stefanos Tsitsipas' dream run at the Rogers Cup continued on Friday as the teenager toppled defending champion Alexander Zverev 3-6, 7-6(11), 6-4 to reach the semi-finals in Toronto.
Greek teenager Stefanos Tsitsipas secured the biggest win of his career when he sent Wimbledon champion Novak Djokovic packing in the third round of the Rogers Cup with a stunning 6-3, 6-7(5), 6-3 win on Thursday.
Defending champion Donna Vekic, of Croatia, earned a hard-fought win over British wild card Gabriella Taylor 7-5, 5-7, 7-6(3).
A summary of Friday's tennis action from around the world.
World No 55 Haase improved to a 2-2 career record against Zverev, including victories in their last two meetings.
Under the lights on the stadium court, Williams smashed 39 winners to defeat Azarenka 7-5, 6-3 in a rematch of the 2016 final, which the Belarusian won.
IMAGES from the matches played at the Miami Masters on Sunday
World number two Simona Halep beat Maria Sharapova 6-2, 6-2 in the China Open third round on Wednesday for her first win over the Russian in eight attempts.
Images from Saturday's action at the Australian Open.
'This was the first time that I played points and that was too much for me today'
The 33-year-old left-hander from Luxembourg had lost all five of his previous tour finals but prevailed at the sixth attempt in the Australian Open warm-up event at the Olympic Tennis Centre.
Venus Williams and CoCo Vandeweghe won the opening singles matches to give holders the United States a commanding 2-0 lead in their Fed Cup World Group opener against the Netherlands in Asheville, North Carolina on Saturday.
Second seed Sloane Stephens was shocked 2-6, 6-4, 6-2 by Germany's Andrea Petkovic in the second round of the Citi Open on Wednesday, disrupting the American's buildup to her US Open title defence.
Images from Day 6 of the Australian Open in Melbourne on Saturday.
American qualifier Sachia Vickery completed an astonishing comeback to stun third seed Garbine Muguruza 2-6, 7-5, 6-1 in a second-round win at the BNP Paribas Open in California on Friday.
Spain's Rafael Nadal was at his dominant best against Pablo Carreno Busta on Saturday, brushing aside his compatriot 6-1, 6-2, 6-4 to move into the fourth round at the Australian Open. Images from Day 6 of the Australian Open at Melbourne Park on Saturday.
World number one Simona Halep swatted aside American Nicole Gibbs while Maria Sharapova was flawless in her straight sets victory over Romania's Mihaela Buzarnescu in the opening round of the Shenzhen Open on Monday.
A summary of Thursday's play at the US Open.
The Danish World No 3 ended 2017 with the biggest title of her career in Singapore and returned a day after thrashing Madison Brengle in her season opener to hit 21 winners against eight unforced errors in the 53-minute win over Martic.
Images from matches played on Day 5 at the Australian Open in Melbourne Park on Friday
IMAGES from the matches played on Day 4 of the Wimbledon Lawn Tennis Championships at All England Lawn Tennis and Croquet Club on Thursday
The returning Scot also announced his withdrawal from next week's Rogers Cup in Toronto.
Images from Day 5 of the US Open in New York on Friday
IMAGES from matches played on Day 7 of the French Open at the Roland Garros in Paris on Saturday