Olympic silver medallist comes from behind to beat fellow Japanese Sota Yamamoto in Espoo, Finland
The Olympic silver medallist from PyeongChang 2018 trailed fellow Japanese Sota Yamamoto after the short program.
But it was Uno who came out on top to claim his first victory of the new season with Canada's Roman Sadovsky taking the last spot on the podium in the ISU Challenger event.
And he was in danger of suffering another defeat here as Yamamoto held a narrow lead after setting a big personal best in the short program.
The 19-year-old broke his ankle in March 2016 just weeks after winning gold at the Youth Olympic Games in Lillehammer.
He needed three operations before returning to the ice.
Yamamoto won last year's Asian Open, another Challenger Series event, and finished sixth in the NHK Trophy where Uno took victory.
Both skaters live in Nagoya and know each other well with Yamamoto taking bronze behind Uno in the 2015 World Junior Championships in Tallinn, Estonia.
Back in northern Europe, Yamamoto scored 92.81 in an excellent short program with Uno scoring 92.28 to leave him just 0.53 behind.
Uno, just two years older than Yamamoto, stepped onto the ice for his free skate with just his younger challenger to follow.
He landed a quad flip after taking a step on his opening triple Salchow, before landing a triple Axel and a triple loop.
A fall on a quad toe loop was a setback but he bounced back with a double Axel-triple toe loop combo followed by another triple Axel.
It may not have been perfect but it was still an impressive skate from Uno who scored 162.95 to set the target with 255.23.
Yamamoto went last knowing exactly what he needed to do.
He started brilliantly, landing a quad Salchow-double toe loop combination, but then it all unravelled somewhat.
The teenager fell on a quad Salchow and then a quad toe loop before hitting the ice twice more as he attempted triple jumps.
That left Yamamoto with a score of 130.43, well down on Uno, but his total of 223.24 was just enough for second place with Sadovsky third on 222.23.
1 Shoma Uno 255.23
2 Sota Yamamoto 223.24
3 Roman Sadovsky 222.23
4 Jimmy Ma 213.49
5 Aleksandr Selevko 206.81
6 Sergei Voronov 206.19
7 Andrei Lazukin 203.91
8 Roman Galay 193.11
9 Edrian Paul Celestino 191.45
10 Christopher Caluza 187.43
While Yuzuru Hanyu continues to lead the way for Japanese male figure skaters, Uno and Yamamoto have shown that there is plenty of talent waiting in the wings.
Uno makes his 2019-20 Grand Prix debut in the Internationaux de France at the start of November before making a quick reappearance at Moscow's Rostelecom Cup two weeks later.
Yamamoto is currently only assigned to the NHK Trophy from November 22-24 where Hanyu will complete his Grand Prix regular season after making his bow at Skate Canada from October 18-20.
October 18-20 - Skate America, Las Vegas
October 25-27 - Skate Canada, Kelowna, British Columbia
November 1-3 - Internationaux de France, Grenoble
November 8-10 - Cup of China, Chongqing
November 15-17 - Rostelecom Cup, Moscow
November 22-24 - NHK Trophy, Sapporo
December 5-8 - Grand Prix Final, Turin