Defending champion and former World No 1, Angelique Kerber, met the talented teenager, Naomi Osaka, from Japan and was shown the exit door at the US Open.
It was a bad draw against the ferociously talented 19-year-old, but the manner in which the 29-year-old performed was incredibly disappointing.
It was a disastrous start for the German, who struggled on her serve throughout.
Kerber had added a second coach for the US Open in a late-season shakeup, but to no avail.
When it was 4-1 today I was thinking, 'I really hope I don't do what I did last year' and that let me focus a lot Naomi Osaka
The German had not won a tournament since her 2016 triumph at Flushing Meadows, and said she wanted to change things up, but defeat continued to stare her in the face.
She was coached by Benjamin Ebrahimzadeh between 2013 and 2015, during a temporary split with her current coach.
“We practice,” she said. “He [worked] with me for, like, a long time and we decide, ‘OK, I have to have something new.’ But Torben [Beltz] is still in my team.”
Having reached No 1 a year ago, she has since dropped to No 6 in the rankings, leading her to look at doing something different.
Kerber also trained for the hard-court season at Patrick Mouratoglou’s academy.
“It’s great for me to get something new again, and [I was] working really hard there,” she said.
“We decide that Benny can help me here at this tournament, so he is like part of my team for this tournament.”
Sadly, the left-hander isn’t the player she was twelve months ago and it showed.
Osaka, however, has power in spades and is precocious enough to believe she can win.
She had a breakthrough year in 2016 when she ascended to number 42 in the world.
The 19-year-old was born in Japan to a Haitian-American father and a Japanese mother, but the family moved to the US when Osaka was three.
She has lived and trained there since then and despite playing under the Japanese flag is as American as apple pie.
She holds dual Japanese and American passports, but represents Japan in international competition, although she barely speaks a word of Japanese.
When she’s 22, however, Osaka will be forced to choose one nationality by Japanese law.
On this day, she took the first set 6-3 from the sixth-seed under the roof at Arthur Ashe Stadium, with play suspended at least until 3 pm on all other courts because of rain.
Kerber hit five double faults and won just two points behind her second serve as Osaka found a way through before serving out the opener.
She just grew in confidence from that point on and completely blew Kerber away to secure the biggest win of her career.
She had forced the initiative, had an answer for everything Kerber threw at her and emerged the victor, 6-3 6-1, leaving the German bemused and ruing the fact that she just became the second defending women’s champion to lose in the first round behind Svetlana Kuznetsova in 2005.
Kerber’s fight barely lasted to 3-3, as Osaka dictated the pace and opened up her frailties.
A consistent base-liner in her glory days, Kerber delivered just 8 winners to 18 unforced against the Japanese teenager, who produced a huge forehand pass to seal that first set.
Osaka, who reached the third round on her US Open debut last year, showed enough power and pride to extend her lead as Kerber simply drowned under the barrage of winners and lost for the second time this year in the first round of a Grand Slam event.
The German became the third top 10 casualty of the tournament, as she dwelled on how tough it is to defend a Grand Slam title.
She re-invented herself last year and was rewarded with the top ranking in the world, and now, as she plummets down into the teens, must re-invent herself again if she is to remain a contender in the future.
Osaka, however, can look forward to a good run in the Big Apple.
“It means a lot, especially since last time I was here.,” she said, referring to leading Madison Keys 5-1 in the final set in round three of last year’s US Open before losing.
“This court has not given me fond memories but hopefully this overtakes that.
“When it was 4-1 today I was thinking, ‘I really hope I don’t do what I did last year’ and that let me focus a lot.”
As for the stats, Kerber struggled badly with her second serve, winning only 37% of points behind it, while Osaka hit 22 winners to Kerber’s 9 when the German notched up 23 unforced errors in a erratic display.
It was all over in just 65 minutes.
Elsewhere Yanina Wickmayer, who is still working with Kim Clijsters, snatched an excellent 6-3 6-1 win over Lesia Tsurenko, a Ukrainian who got herself inside Top 30 for first time in career and was defending a fourth round reached last year.
The recent Hall of Famer Clijsters is participating in the legends event here and is helping Wickmayer as she did at Wimbledon.
“I’m doing it purely from friendship,” said the US Open three times champion. “It is not the first time [that] I help her.”
It must have been an emotional day for Clijsters since on this day, 29 August, 2012, she ended her career for the second and last time on one of her favourite stages in the sport, losing to Laura Robson.