Serena Williams believes that she is mainly to blame for the defeat in the US Open final. The American did not play well enough to restrain Canadian teenager Bianca Andreescu.

Nineteen-year-old Andreescu, who was in the main schedule in New York for the first time and played her first Grand Slam final ever, won in two sets: 6-3 and 7-5.

"When I look back on this in twenty years' time I probably think: it wasn't that bad either. But at the moment I can't live with it, because I don't think I played well," said the grieving American.

The 37-year-old Williams served dramatically. Only 44 percent of her first stores came in. In addition, she made 33 unnecessary errors, including eight duplicate errors.

"I was too little Serena today. He didn't give home today," Williams said. "I now have to see what I can do about it, that it will happen in the future. I regularly asked myself during the game why I played so badly in a final."

Bianca Andreescu could hardly believe that she won her first Grand Slam tournament. (Photo: Getty Images)

"Bianca deserves to win here"

It is the fourth consecutive time that Williams has failed to win the final of a Grand Slam tournament. With a victory she would have come on level with Margaret Court, who is the record holder with 24 titles.

The American lost the Wimbledon final earlier this year at the expense of Simona Halep and last year she also went down in the Wimbledon and US Open finals. She won her last Grand Slam title in early 2017 in Australia.

"I am so close, but at the same time the level I can reach is so far away," Williams sighed. "This is very frustrating. I think I just have to keep fighting and continue as a professional. There is nothing else to do."

Although Williams was disappointed with her own performance, she was full of praise for Andreescu. She predicted a great future for the Canadian. "She plays well under pressure, even though she was certainly not the favorite here. She just keeps on going and gives everything. Today she also put a lot of energy into her game and that is why she deserves to win here."