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Britain's men's and women's No. 1-ranked players Jack Draper and Katie Boulter were both eliminated by their No. 2-ranked compatriots in the second round of Wimbledon on Thursday on a dramatic day dubbed the "Battle of the Brits."

Harriet Dart emerged victorious from a fiercely-contested clash with Boulter while fellow No. 2 Cameron Norrie claimed an upset win of his own over Draper.

Later on Thursday, British tennis legend Andy Murray's Wimbledon farewell got off to a difficult start as he was knocked out of the men's doubles in the first round alongside his older brother Jamie with a 7-6(6), 6-4 loss to Australian pair Rinky Hijikata and John Peers.

The two-time Wimbledon singles champion had his movement limited by back pain throughout the match and had to rely on his service game as he battled through the straight-sets defeat that potentially leaves him with one match left to play at the tournament.

Dart's 4-6, 6-1, 7-6 (8) victory in a three-set thriller that was decided by a dramatic 10-point tie break, was just her second success against No. 1 Boulter. The pair, who were born four days apart in 1996, had never previously faced off at a major and Boulter had never before been beaten by a fellow Brit.

The Billie Jean Cup teammates wrestled for control of the match in the opening games as both surrendered opportunities to convert break points. However, a crucial missed backhand from Dart in the fifth gave Boulter a 3-2 advantage that she converted into a set lead via her impressive service game.

But Dart came roaring back in the second, taking just 17 minutes to go 4-0 up, allowing a solitary game to slip before taking the match to a deciding third set.

A marathon fifth game in which Dart converted break point at the sixth time of asking seemed as if it would prove decisive, but Boulter rediscovered her form at the vital moment, breaking back in the eighth to level the scores at 4-4.

There was still nothing to separate the players after 12 games in the third set and almost three hours' worth of play on No. 1 Court, resulting in a 10-point tie break that Dart edged 10-8 to move into the third round and into the top 80 in the world rankings for the first time.

"I wear my emotions on my sleeve so you see everything how I'm thinking, unfortunately, but I'm so happy to be able to get through," Dart said.

"My head-to-head is absolutely woeful against Katie Boulter so I wasn't expecting too much but at the same time I just tried my best out there and even though I was down in that tie-break I just thought: 'Give it everything, no regrets' and I'm really pleased to be able to battle through."

Draper's showdown with Norrie had seemed as though it would follow a similar pattern as both players traded games before Norrie found his groove after winning the first-set tie break on his way to a 7-6 (3), 6-4, 7-7 (6) win over his younger opponent.

Norrie hardly put a foot wrong in his straight-sets victory, playing his full repertoire of shots and remaining composed whenever it looked like Draper might be making a comeback. A 8-6 win in the third-set tiebreak proved enough to send him through to the third round at Wimbledon for the first time since he reached the semifinals in 2022.

The defeat will have come as a bitter blow to British No.1-ranked Draper who had hoped to make a deep run in the championships off the back of an eye-catching win over Carlos Alcaraz at Queen's on June 20.

Norrie has now beaten Draper on all three occasions in which the two left-handers have faced off.

Earlier on Thursday, wild-card Jacob Fearnley put up a fight but was eventually outclassed by seven-time Wimbledon champion Novak Djokovic 6-3, 6-4, 5-7, 7-5.

Djokovic, who has made a miraculous recovery from knee surgery to play at the championships, was made to work for his spot in the third round by the 22-year-old Brit who produced the best performance of his career despite the defeat on Centre Court.

Lily Miyazaki's singles campaign ended in the second round as she was thrashed 6-0, 6-0 by Russia's Daria Kasatkina on Court 18.

Fourteenth seed Kasatkina, winner of last week's Eastbourne title, was in a merciless mood as she dispatched Miyazaki in less than an hour.

Information from Reuters contributed to this report