Kostornaia wins in Turin from Anna Shcherbakova with Alexandra Trusova taking third after becoming the first woman to land a quad flip in competition
Alena Kostornaia's dazzling debut senior season continued with victory at the 2019 Grand Prix of Figure Skating Final.
The 16-year-old followed up her world-record score in the short program with a foot-perfect free skate to top an all-Russian podium.
Kostornaia was competing against three of her training partners in Turin, two of whom jump quadruples, but she kept her cool to deliver a clean and polished performance, earning a personal best score of 162.14 for a world record total of 247.59.
Alongside her on the podium were Anna Shcherbakova and Alexandra Trusova, while Olympic champion Alina Zagitova - second after the short program - finished in sixth place after a disappointing free.
All four Russians train together in Moscow under coach Eteri Tutberidze.
"This competition was a challenge for me because it is the third competition at this high level. It's really cool that I came to be first." - Grand Prix Final winner Alena Kostornaia
Kostornaia, Shcherbakova and Trusova - nicknamed the 3A - had won all six of the Grand Prix competitions between them in their first senior season.
Trusova made history as the first woman to land a quadruple flip in competition but it wasn't enough to put her on top of the podium.
The double world junior champion, fifth after the short program after a fall on a triple Axel attempt, attempted an astonishing five quads in the free but popped the Salchow and fell on the toe loop.
Trusova admits she was affected by nerves and said, "I skated the program very badly, apart from being the first ever to land a quad flip. I think it was nerves. I rushed at my Salchow.
"Three quads is not enough for me now. I know I can do more. It's a pity it works in practice and not in competition." - Alexandra Trusova
Skating after Trusova, Shcherbakova fell as she tried to become the second woman to land the quad flip.
She did, however, land two quad Lutzes and her personal best score of 162.65 won the free skate and secured second overall.
Shcherbakova said, "In general I am pleased but I have a bit of a bitter taste because the flip didn't work out.
"Despite it not working out, I am glad that I stayed focused and performed the rest of the program right."
Unlike her two fellow medallists, Kostornaia managed to stay on her feet proving that quads are not essential to success.
She did land two triple Axels in her free skate and said at the post-skate press conference, "When I’m doing the jumps in my program, I’m not really paying much attention to what is going on around me.
"But as soon as the jumping part is finished I’m aware of the audience, I hear how they are cheering and that’s nice."
Earlier, defending Grand Prix Final champion Rika Kihira came back fighting after a disappointing short program, attempting a quadruple jump for the first time in competition.
The Japanese teen fell on the quad Salchow, her opening jump, but skated cleanly for the rest of her program and ended the competition fourth overall.
The USA's Bradie Tennell finished fifth ahead of Zagitova, who saw multiple jumps called under-rotated after an early fall on a double Axel.
After a mistake in the rhythm dance, the duo were back to their formidable best with a score of 136.02, just shy of their world record set at NHK Trophy last month.
"We felt amazing tonight," said Cizeron. "Seeing so many people cheering for us in this historic rink felt really special.
"We had an amazing feeling. Everything went really smoothly and we're just really proud of us and really proud of our team."
As for what now, Papadakis said, "The main thing is eat. That's what I've been thinking all week because I'm in Italy and the food is so good and I've been thinking, 'I can't wait for this competition so I can eat three pizzas in a row or whatever'. I'm pretty obsessed with that right now."
Hubbell and Donohue, skating to music from 'A Star Is Born', gave their best performance this season with a score of 125.21.
All three duos train together in Montreal under coaches Marie-France Dubreuil, Patrice Lauzon and Romain Haguenauer.
Cizeron added: "Our team from Gadbois did the 1-2-3 so it's a pretty special final for us."