He made his debut in SASUKE 18 where he performed well in the race, beating competitors such as Nagano Makoto and getting a very high number, #91. During the competition, he was fast. Although he got caught on the Pole Maze, he was able to pass it in good time. When he got to the Jumping Spider, he hit the trampoline correctly, but failed to get his legs up to the walls.
He returned in SASUKE 19, wearing #71. Wearing all black (resembling Nagano Makoto), he made it to the Pole Maze but lost a lot of time there as the pole got stuck. He eventually got out with little time left and was able to face the Jumping Spider again. This time the obstacle was much harder, yet he was able to beat it, unlike many that day. He made it to the new Half-Pipe Attack but lost his footing and missed the rope.
He has competed in SASUKE 21 and again failed the Jumping Spider. In SASUKE 22, he was unable to scale the Soritatsu Kabe and timed out on the obstacle. He was cut from both broadcasts. However, in an interview with Morimoto, his results were revealed.
At the age of 19, Morimoto returned to SASUKE for the 27th competition. Although he was digested, he finally cleared the First Stage as many did for their first time that day. In the Second Stage, Morimoto would fail the Metal Spin.
In SASUKE 29 he had number #79. He cleared the First Stage for the second straight time, with 9.69 seconds left. Morimoto then broke the streak of 10 straight Second Stage failures before him by speeding through the course to clear with just 0.81 seconds remaining. The Third Stage was timed to clarify the competitor, if any, that cleared the stage in the fastest time. He struggled for over a minute on the Iron Paddler. However, because of the timer, he was allowed to rest for as long as he wanted, unlike in other competitions where a competitor can only rest for 30 seconds. After resting for over 5 minutes, he became the first person to beat the Crazy Cliffhanger. He cleared the next two obstacles, the Curtain Cling and the Vertical Limit with ease. However, on the Pipe Slider, he almost cleared but his foot slipped and fell down in the water.
He went the farthest in the tournament, which has led to him being selected as Japan's representative in SASUKE ASEAN Open Cup 2014, which was held in February 2014 in Kuala Lumpur, Malaysia. There, he put on a strong showing for Team Japan and earned a silver medal.
With all this, he was invited back to SASUKE 30 and wore the coveted #3000 (#100 In regular tournaments). In SASUKE 30 he cleared the First Stage with 11.16 seconds left on the clock. In the Second Stage Morimoto took the raised time limit too much for granted and as a result timed out on the Wall Lifting.
Morimoto also competed in American Ninja Warrior: USA vs. The World. He first competed in the Second Stage of the first match against Brian Arnold and Stefano Ghisolfi. Morimoto started strong, but due to his height he was unable to catch the Butterfly Wall and failed the match after Brian Arnold cleared the stage. In the Third Stage, Morimoto competed in the Second Match with Joe Moravsky and Stefano Ghisolfi. Morimoto managed to clear the stage and according to sources should've won his match as he finished a few seconds faster than Ghisolfi, however, NBC used cutaways to the crowd to add time to his run that he didn't take, thus making it seem as if he went slower than Ghisolfi.
Morimoto donned the #91 bib for SASUKE 31, the same starting position as the tournament he debuted in. He beat the First Stage with little trouble, clearing with 9.26 seconds left. In the Second Stage, he got revenge on the Wall Lifting and cleared with 19.41 seconds, the fastest time of the day. He put up a strong performance in the Third Stage, clearing the Iron Paddler, which he struggled two years ago, with ease. He cleared the Crazy Cliffhanger a second time, becoming the only man to ever do so. He then struggled with the Vertical Limit Kai, but passed it, and got his revenge on the Pipe Slider, landing with both feet on the landing platform. He made it to the Final Stage for the first time, becoming the only competitor to do so in that tournament. In the Final Stage, Morimoto showed great speed. He finished the Spider Climb at a great pace, reaching the Tsuna Nobori with around 20 seconds left. He climbed with a blistering speed but ended up having to push his body to reach the final button. This did not cause him any trouble as he achieved kanzenseiha with 2.59 seconds left, becoming the 4th person in history to enter the honor roll and the first competitor to beat the Final Stage in his first attempt since All-Star Akiyama Kazuhiko sixteen years ago. He did not compete in Sasuke 32 due to college and work.
In a Nico Nico broadcast with Inui, it was confirmed that Morimoto would return for SASUKE 33, where he would be #100. Morimoto marked his return with a First Stage clear with 6.60 seconds left, before passing the Second Stage with 16.51 seconds remaining - a time quicker than anybody else. In the Third Stage, with the other competitors already eliminated, Morimoto carried out his attempt as the last man standing. He got past the Drum Hopper Kai, but was unable to beat the Flying Bar, and the tournament ended with no Third Stage clears.
|18||91||Failed Jumping Spider (First Stage)|
|19||71||Failed Half-Pipe Attack (First Stage)|
|21||52||Failed Jumping Spider (First Stage)||All Cut|
|22||27||Failed Soritatsu Kabe (First Stage)||All Cut. Time Out.|
|27||84||Failed Metal Spin (Second Stage)||Digest.|
|29||79||Failed Pipe Slider (Third Stage)||Failed Jump.|
|30||3000||Failed Wall Lifting (Second Stage)||Time Out. Third Wall.|
|31||91||Kanzenseiha||2.59 seconds left. Last Man Standing|
|33||100||Failed Flying Bar (Third Stage)||Misjudged the distance of transition from first to second rung. Last Man Standing.|