Two-time reigning Olympic men's gymnatics champion Kohei Uchimura failed to qualify for the final of the six-apparatus event on Friday, the opening day of the Japan National Championships.

Uchimura, also a six-time world all-around champ, placed 37th and did not advance to Sunday's final, which will be contested by the top-30 gymnasts.

The three-day national championships at Takasaki Arena serves as qualifiers for October's world championships in Stuttgart, Germany.

The 30-year-old Uchimura, who revealed Thursday he has pain in both shoulders, had an error-prone performance, falling in both the vault and the parallel bars. He scored 80.232 points for a six-routine total, 5.334 points behind reigning national champion Kakeru Tanigawa, who topped the qualifiers.

"I did have shoulder pain, but I was also unable to get in the practice I'd hoped for," Uchimura said. "I'm not particularly bitter about this. I just have to build on this going forward."

It marked the first time since 2005, when Uchimura made his debut at the nationals, that he has failed to qualify for the final.

Last year, Uchimura failed to win his 11th straight national championship, finishing third behind Tanigawa, who became the youngest national champion at 19 years and two months.

Uchimura qualified for last year's worlds in Doha but pulled out of the individual all-around event due to a right-ankle injury sustained the previous month. He won silver in the horizontal bar for his 21st world medal.