"I was very sad and emotionally I was really not on court," Jankovic said. "I really tried my best to be there and to try to play but it was really hard."
An error-filled folly with 14 breaks of serve nearly went to fifth seed Jankovic, but she squandered two match points in the final tie-breaker with forehands beyond the baseline and lost two points later on an ace by Shvedova.
"I was not happy on the court. I was really suffering," Jankovic said. "I tried to think about my tennis, but I felt like I was so late and so slow. I couldn't even watch the ball. That was my problem.
"There are more important things in life than tennis. When you think about it, this is just a small event compared to somebody in your family who dies."
Jankovic's heartache concluded a Grand Slam season of frustration for the 24-year-old from Belgrade who finished No. 1 in the world last year and reached her first Slam final on the same Ashe Stadium court.
Jankovic, 38-14 this year, bowed out in the fourth round at the Australian and French Opens and was upset by US teen Melanie Oudin in the third round at Wimbledon. A US Open tuneup title at Cincinnati appeared to right the ship.
But nothing could prepare her for a shocking loss more devastating than anything ever delivered on a tennis court.
"I was really tired and tight. I moved really badly. When you are mentally affected by this kind of thing, I guess that all goes together," Jankovic said.
"When you are sad, when you are down, you're not the same person. You don't move as well. You don't hit the ball as well. My head wasn't really there. It was like a shadow of myself. But what can you do?"
Jankovic was so devastated that she could barely speak with her mother, who called from Serbia with the sorrowful news after flying from Jankovic's side Wednesday.
"I was just crying. It's really hard," Jankovic said. "I was really down. It's normal because I'm an emotional person, so it's not easy.
"It's very difficult situation. My mom, as well, is recovering from surgery. We are all down."
Shvedova will next face Argentina's 40th-ranked Gisela Dulko for a berth in the round of 16 in a draw quarter suddenly wide open with struggling world number one Dinara Safina the lone remaining seed.
Jankovic will put tennis behind her and fly home to mourn with her family.
"Life goes on and I have to try to stay positive as much as I can, get through this," Jankovic said.
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