Kazakhstan began its Billie Jean King Cup finals campaign with victory over hosts Britain on Tuesday while seven-time champions Australia saw off Slovakia in the opening tie.
Formerly called the Fed Cup, the event was renamed in honor of American 12-time major winner King and restructured into a 'World Cup of tennis' format concluding with 12 nations competing over one week for the title.
Yulia Putintseva and Briton Katie Boulter looked evenly matched when they took one set apiece before the Kazakh 27-year-old stepped up a gear and stormed into a 4-0 lead in the decider before sealing a 4-6 6-3 6-2 victory.
Wimbledon champion Elena Rybakina then sealed the tie in 73 minutes by beating Harriet Dart, winning seven games in a row at one point to win 6-1 6-4 and give Kazakhstan an unassailable 2-0 lead.
"I think she's an incredible player. She's the Wimbledon champion for a reason, and she brought a very high level from the start. I thought she played a very clean match," Dart told reporters.
"I really don't think I played that bad. I thought that she kind of took things into her own hands. She's definitely one of the few players on the tour that can kind of take the match out of your hands."
Britain was dealt a huge blow last month when former U.S. Open champion and their highest-ranked player Emma Raducanu pulled out of the team because of a wrist injury.
Britain next faces Spain on Thursday.
Australia win
Earlier, Australia's Ajla Tomljanovic and Storm Sanders won their singles matches in straight sets in their 2-1 win over Slovakia in the opening tie of Group B.
Sanders beat Viktoria Kuzmova 6-4 6-3 while Tomljanovic eased past Anna Karolina Schmiedlova 6-1 6-2.
Tomljanovic has had a good season in the second half of the year, capped by her quarter-final runs at Wimbledon and the U.S. Open. She has since reached a career-high ranking of 33.
"If I have to put it to one thing, it's just where my head's at in my life. I think that translates to the court. I'm happy, tennis is fun again," she said.
"Even when I'm losing, I'm finding joy, which is really all it's ever been and it's supposed to be. I lost it a little bit there for a year or so. But it happens, it's OK."
Slovakia did manage to get on the board when the doubles pairing of Kuzmova and Tereza Mihalikova beat Sanders and Ellen Perez 2-6 6-3 10-6.