Maria Sharapova's first Grand Slam tournament in 19 months ended with defeat by Anastasija Sevastova in the US Open fourth round.
Latvia's Sevastova, the 16th seed, won 5-7 6-4 6-2 to reach the quarter-finals in New York.
The 27-year-old will play Sloane Stephens in the quarter-finals, after the American beat Julia Goerges.
Sharapova, ranked 146th after returning from a doping ban in April, was given a wildcard into the main draw.
"It's been a really great ride in the last week," said the 30-year-old.
"I can take a lot from this week. It's great to get that major out of the way. It was an incredible opportunity. I'm very thankful for the opportunity.
"I did my best. I can be proud of that."
The 2006 champion had played just one match since May coming into Flushing Meadows, with injuries forcing her out of the grass-court season and US Open build-up.
She played superbly to upset world number two Simona Halep on the first day of the tournament, and then beat Timea Babos and Sofia Kenin on her way to the last 16.
-Day seven text coverage as it happened
-Live scores, schedule and results
-Williams reaches quarter-finals
-Carreno Busta ends Shapovalov's run
'As long as I have that desire, I'll be there'
Sharapova's presence in the main draw divided opinion from the moment her wildcard was announced, but she was unperturbed as she racked up three wins in a row for the first time since her comeback in April.
The Russian was warmly received by spectators and organisers were happy to draw on her star power, putting her on the main Arthur Ashe Stadium for all four of her matches.
That decision was described as "questionable" by fifth seed Caroline Wozniacki, but Sharapova simply responded that scheduling was not her responsibility.
Asked after Sunday's defeat if she felt as though she had a target on her back, Sharapova responded: "I feel like I'm really beyond that. I mean, there's no other way to explain it.
"I think there's only a way to show it on the court, because that's what really matters to me.
"I have so many things in my life that I've already been able to experience, but there's a desire to keep going for more, and to keep training and to keep living through these moments out on these courts.
"That's special and that's meaningful. As long as I have that desire, I'll be there. That's what's important to me."
I just kept fighting - Sevastova
Sevastova beat Garbine Muguruza and Johanna Konta on the Arthur Ashe Stadium 12 months ago, and the 5ft 5in Latvian's defensive skills and ability to create angles ultimately derailed Sharapova.
"The first set was very close, it could have gone either way," said Sevastova.
"She played unbelievably throughout the first and second set and I just kept fighting, running after every ball, and just stayed there."
Sharapova ended the match with 51 errors to 42 winners as she pressed too hard in trying to break down Sevastova's brilliant defence.
The Latvian went close to taking the first set after coming back from 4-1 down, but Sharapova clinched it with two magnificent forehands in game 12.
The momentum had already begun to swing though, and Sevastova would level thanks to a single break at 2-1 in the second - in one rally lobbing Sharapova twice, prompting the Russian to scramble left-handed in desperation.
A six-minute bathroom break ahead of the decider apparently did not have the desired effect as Sharapova quickly fell 3-0 down.
She had said after her opening match that "this girl has a lot of grit", and it was in evidence as she cut the deficit to 3-2, but in the end Sevastova had too much.
Sharapova fought off three match points before a big first serve left the five-time major winner flailing at a return that flew wide after two hours and 17 minutes.
Analysis - a match too far for Sharapova
BBC Sport tennis correspondent Russell Fuller
Sevastova carved out a hard-earned victory with some mighty defence, and clever use of the drop shot and slice to drag Sharapova into the net.
The Russian was outstanding in patches, but lost her way completely in the deciding set. Her forehand simply disintegrated, as she hit 18 unforced errors and just four winners.
Sharapova is projected to return to the world's top 100 as a result of her run to the fourth round. She won three more matches than many thought she would after a summer disrupted by injuries, before a lack of match practice appeared to catch up with her.
And even though the US Open may not appreciate this just now, it is encouraging for the WTA Tour that a current top 20 player is able to close out victory over an opponent who may have won five Grand Slams, but has featured in only five events in the past 19 months.