Reigning world champion Ilia Malinin delivered a season-best short program on Thursday night, giving the young American star a slim lead over Japan's Yuma Kagiyama in what has quickly become a two-man race to this year's title.

The 20-year-old Malinin delivered a pair of quads and a brilliant triple axel to score 110.41 points, just over three points off the world record set by Nathan Chen at the 2022 Winter Olympics. It was enough to keep Malinin in first when Kagiyama followed him with a resplendent program that resulted in a score of 107.09 — about a point off his career-best.

Mikhail Shaidorov of Kazakhstan was a distant third with 94.77 points heading into Saturday night's free skate, which will wrap up the final world championships before the Milano-Cortina Olympics next year.

The high-flying Malinin, who has not been beaten since 2023, has become the clear-cut favourite to succeed Chen at the Winter Games. And he certainly doesn't seem to mind the pressure, performing with a sort of swagger that belies his age.

As Malinin wrapped his short program, set to "Running" by American rapper NF, the TD Garden crowd stood in ovation.

WATCH | Malinin leaps to large early men's short program lead:

American 'quad god' Ilia Malinin jumps out to big world championship lead in Boston

Malinin set a new personal best score of 110.41 points to win the men's short program, at the world figure skating championships in Boston.

Canada's Sadovsky just misses season-best score

Roman Sadovsky of Vaughan, Ont., posted an 80.25, just shy of a season-best, to rank 15th after his solid skate to "Unconscious" by Charlie Winston.

"Overall, a really positive experience, really good energy here in the crowd — lots of Canadian flags," said Sadovsky, who placed 19th at worlds in Montreal last year.

The 25-year-old qualified for Saturday's free skate and secured one men's event entry for Canada at the 2026 Winter Games. He'll need to climb into the top 10 to earn his country a second provisional spot.

WATCH | Sadovsky sits 15th after men's short program:

Canada's Roman Sadovsky sits in 15th place at the world figure skating championships

Roman Sadovsky of Vaughan, Ont., is in 15th place after the men's short program, at the world figure skating championships in Boston.

The world championships continued Thursday night, when the first medals were to be awarded following the pairs free skate. Riku Miura and Ryuichi Kihara of Japan had a nearly two-point lead over Sara Conti and Niccolo Macci of Italy after their short program as they try to win back the world title they held two years ago.

One of the subplots to the world championships is how many spots each country can secure for the Olympics. The formula is relatively complicated, but for countries such as the U.S. with three competitors at worlds, the top two placements must total 13 or less for that nation to receive the maximum of three spots at the Winter Games.

Malinin is certain to give the Americans one good score. The other will depend on the performances in Saturday night's free skate for Andrew Torgashev and Jason Brown, the 30-year-old, two-time Olympian who continues to defy his age.

WATCH | Malinin speaks to CBC Sports' Devin Heroux after season-best score:

Ilia Malinin overcomes nerves to win men's world championship short program

American Ilia Malinin spoke with CBC Sports' Devin Heroux, after setting a new personal best score of 110.41 points to win the men's short program, at the world figure skating championships in Boston.

Nevertheless, Brown was all smiles after a solid skate amid a trying season. He's been dealing with boot issues that forced him to withdraw from the U.S. championships in January, and only recently did he finally get his equipment sorted out.

"You know what? It felt great," Brown said. "I'm proud of the fight that I gave this season. You know, every single time I got knocked down, my coaches and sports psych and my family would like, rally behind me, like, `No, we're going to keep pushing. We're going to figure it out.' And so out of that, oh my gosh, it's so special."

That Figure Skating Show | Previewing the 2025 world championships in Boston:

That Figure Skating Show previews Boston 2025

The 2025 World Figure Skating Championships are in Boston where Amber Glenn and Ilia Malinin get to compete on home soil. Piper Gilles & Paul Poirier look to win elusive world gold and Deanna Stellato-Dudek & Maxime Deschamps defend their title. Olympic quota spots are on the line for Canadian single skaters and we hear from Devin Heroux, our man on the ground at Worlds.