United Cup: Defending Champions USA Beat Battling Britain

Jessica Pegula and Taylor Fritz had to fight through a deciding doubles match to conclude a 2-1 defeat of Britain on Sunday for the United States to stay in title contention at the United Cup. The defending champions, who won the trophy last January over Italy, earned a 1-6, 7-6 (7/5), 10-7 mixed doubles win to claim victory in Perth after the sides split the singles. "We have a team energy from last year here, we don't want to take a loss and let it die," said Fritz, who was broken twice in the opening set.

World number five Pegula added: "To get a win in this fashion after such a long day (on court) brings back a lot of memories.

"It was a big win today, especially after losing such a tough singles match."

Britain, who beat Australia to open their tournament account, took a 1-0 lead when Pegula crashed 5-7, 6-4, 6-4 to Katie Boulter in the singles.

It was Boulter's first win over a top-five player on her seventh attempt after she bounced back from a set and double-break down.

"This was a very hard match for both of us," said the 56th-ranked Boulter. "I play my best tennis when I'm smiling and having fun.

"I kept trying to get over the line. I thrive in a team atmosphere... so many tennis heads giving information. It helps you to think clearly."

Pegula's 10th-ranked teammate Fritz kept the tie alive despite a thigh strain he blamed on over-training, defeating Cameron Norrie 7-6 (5), 6-4.

"I strained something but got through it," said Fritz. "Cam and I have played so many times (14). It's always a battle, always close."

World number one Novak Djokovic opens his season for Serbia later against China's Zhang Zhizhen, with the Chinese team on a high after beating the Czech Republic 3-0.

In Sydney, Leylah Fernandez led