Madison Chock and Evan Bates claimed ice dance gold to make it a clean sweep for the United States on the closing day of competition in Grenoble.
Malinin attempted six different quad jumps and, although not all of them came off, he lived up to his self-proclaimed nickname 'the Quad God'.
The 20-year-old world champion went into the free skate with a yawning 12 point cushion over Yuma Kagiyama, the 2022 Olympic silver medallist, after the short programme.
Despite being marked down for some missed jumps in a routine which featured a full back flip, he wound up with a 292.12 total to comfortably hold off Kagiyama (281.78). Another Japanese, Shun Sato, took bronze (270.82).
"A lot was going on in my mind, I had this idea and this goal I wanted to achieve here," Malinin said.
"I wanted to get on the ice and I hope everyone enjoyed that performance. From now on, my main goal is to clean up everything.
"Merci beaucoup, Grenoble," he added.
Earlier US national champion Glenn extended her slender lead from the short programme in the free skating final, scoring a total of 212.07 points after two performances, which both included her signature triple axel jump.
Glenn was up against five Japanese skaters in the six-competitor final. Mone Chiba took silver with 208.85 points. Defending champion Sakamoto took bronze with 201.13.
Glenn, who won both her Grand Prix events in Angers, France and China this year, had not won an international event before this season and steps into the spotlight just over a year ahead of the 2026 Winter Olympics.
The 25-year-old Texan became the first American woman to win the Grand Prix final, the third major event in the skating calendar after the Olympics and world championships, since Alissa Czisny in 2010.
"It's been a whirlwind of a season and I've struggled with some impostor syndrome – 'oh, no no, that's not me' – but I'm just happy that my hard work is finally showing," Glenn said.
Sakamoto had not been beaten in a major competition since the 2022 Grand Prix final.
The 24-year-old Olympic bronze medallist paid for a fall on a triple toeloop which cost her points in the short programme.
"I'm relieved – there was no big mistake today, so I'm somewhat satisfied," she reflected.
American two-time reigning world champions Chock and Bates dominated the free dance final.
They nailed their jazzy routine to defend their Grand Prix final crown in style with a total of 219.85, over 13 points clear of Italy's Charlene Guignard and Marco Fabbri.
"Each time feels like the best time," Chock said.
On Friday, German figure skaters Minerva Fabienne Hase and Nikita Volodin successfully defended their pairs title.
