Gauff had already defeated another former No 1 – beating Venus Williams in the first round – and the young American completed an astonishing comeback in the third round, saving match points to defeat Polona Hercog 3-6 7-6(7) 7-5.
But last year’s French Open champion Halep, who recorded an impressive straight-sets win over Victoria Azarenka in her last outing, proved too strong recording a straight sets win.
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Good morning and welcome to our live coverage of another day's play at Wimbledon 2019.
As Wimbledon enters its second week, age is all the rage. Roger Federer (at 37 years and 340 days) and Rafael Nadal (at 33 years and 41 days) are both aiming to become the first man to win five Grand Slam titles after turning 30, while Serena Williams (at 37 years and 290 days) will be hoping to become the oldest women’s Grand Slam singles finalist in the Open era.
At the other end of the scale, the remarkable Coco Gauff, who turned 15 only four months ago, is already the youngest player to have come through the Wimbledon qualifying tournament and the youngest to reach the second week here since Jennifer Capriati in 1990.
If she wins her next four matches, starting against Simona Halep in the fourth round on Monday, Gauff would become the youngest champion of a senior event in 142 years of Wimbledon history. The record is held by Lottie Dod, who in 1887 needed to win only three matches to claim the women's singles at 15 years and 285 days.
Every player still in the singles draw plays on the second Monday, hence the phrase 'Manic Monday'!
And here is today's full order of play:
FIRST BATCH OF MATCHES (singles):
Court 2 - Ashleigh Barty (1) vs Alison Riske
Court 3 - Elina Svitolna (8) vs Petra Martic (24)
Court 12 - Barbora Strycova vs Elise Mertens (21)
Court 18 - Shuai Zheng vs Dayana Yastremska
Barty 2-1 Riske*
We'll be keeping you up to date with the progress of world number one Ash Barty out on Court No 2. She plays unseeded American Alison Riske, who with her flat style of play is a tough opponent on grass.
It's with serve so far, though Barty did just escape from a game which was at deuce.
Meanwhile, this is promising signs for the future...
Barty 4-1 Riske*
The Australian breaks to 30, and then holds comfortably to love.
World number one Barty has the early break...
Ash Barty's first game...
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