Chen, the first American men's world champion since 2009, finished with 92.99 points even though he made a mistake on his quad toe loop-triple toe loop combination, which cost him some points. "Clearly I made the big mistake at the end of the program (on the quad toe), something that I could totally have avoided, it's just a little bit of a slip," Chen said. "But I'm glad I'm getting experience, I'm doing the program throughout the season and making mistakes like this so I can keep learning.
"The free (skate) is the most important thing now. What I did in the past just stays in the past. I can't change what I did. So I just have to use what I did and evolve it into the long program." Olympic silver medalist Shoma Uno of Japan was second with 91.67 points and was disappointed with his program.
"It really was not a great performance today," he said through a translator. "I wish I could say there was a reason for that but there isn't any. I just couldn't do my jumps properly." Michal Brezina of the Czech Republic, back in the finals for the first time in seven years, was third with 89.21 points.
Two-time Olympic champion Yuzuru Hanyu of Japan dropped out from the event with an ankle injury. Zagitova's lengthy run of winning each stage of competitions dating back to last season ended when Japan's breakout star Rika Kihira dominated the women's short program with 82.51 points, the highest women's score this season.
"I was able to perform very calmly. Obviously I was very happy with the score," the 16-year-old said through a translator. "Now that I've received such a score in the short, I need to complete my free successfully as well. That's all I would like to focus on for now."
No such calmness for Zagitova of Russia, who finished second with 77.93 points, a substantial margin to make up. "Today I felt a little tense," Zagitova said. "But I'm glad I was able to pull myself together. The tension came from nerves. It all comes from the head. But you just have to go out and do it."
Zagitova's teammate Elizaveta Tuktamysheva was third at 70.65. The finals continue Friday with the men's free skate, the pairs short program and the rhythm dance.