Both Kasai and gold medallist Yuzuru Hanyu set Olympic precedents - Kasai becoming the oldest ski jump medal winner and Hanyu, 19, becoming the first Asian man to take gold in figure skating.
"Burning Wings of Fire," said the Mainichi Shimbun daily of Kasai, who late on Saturday - early Sunday in Japan - won his first individual medal in his seventh Olympic appearance.
He took silver in the team competition at the Lillehammer Olympics in 1994, 10 months before Hanyu was born.
"I just got my silver medal!" Kasai said on his blog early on Monday. "It's quite heavy, much heavier than the team medal I won 20 years ago. It has the weight of all my previous six Olympics in it."
With headlines such as "The Phoenix of the Silver-white World," Japanese media zeroed in on Kasai's stubborn pursuit of his goal at an age well past when many a ski jumper would be more than happy to hang up their competitive skis for good.
Television shows brought in analysts to focus on every aspect of his life and training. One programme even displayed a life-size replica of his yellow lycra suit.
Among the misfortunes he overcame was his mother's death in a fire just before the 1998 Winter Olympics, which were hosted by Japan. In addition, he was left off the team for the large hill competition that year due to an injury and had to watch from the sidelines as his fellow skiers won the gold, a feat that riveted the nation.
"He has always hated to lose," his older sister Noriko told TBS television on Monday. "He has said he hates seeing the footage of those Olympics, which I can understand.
"But his face the other day was really happy. I think he is really savouring it now because of what happened before."
KING OF THE ICE
Celebration of Hanyu's win, Japan's first Winter Olympics gold since 2006, continued unabated from the weekend, when newspapers issued special editions - several with the headline "King of the Ice" - and Prime Minister Abe placed a call to Sochi to congratulate the teen on his victory.
Television stations showed endless replays of his free skate, centring on the moments when he fell, along with his grin as he received his medal.
"I hadn't fallen on a triple flip since I was in junior high. I think it was because I was nervous," Hanyu, who racked up a record score for his short programme, told one station.
"I felt terrible. I was sure I'd lost the gold right there."
Hanyu, whose hometown of Sendai was badly damaged by the March 2011 earthquake and tsunami, has said he feels a responsibility to give back to the area.
He teared-up on one programme when an elderly woman in temporary housing in a devastated town wept as she described the impact of his win.
And like Kasai, who says he intends to return for the 2018 Olympics in South Korea, Hanyu says even a gold medal is not enough incitement to take a well-deserved vacation.
"I really, really want to get back to practicing," he told TBS television less than a day after his win. "I didn't skate the way I wanted, there's still a lot to do.
"Being here at the Olympics has made me love skating even more than before."
- Sports & Recreation
- Ice Skating
- Noriaki Kasai
- Yuzuru Hanyu