He first stepped on the pro sumo [[dohyō]] in July of 2006. Being a diligent trainer, and managing to avoid injury, he rose through the ranks of and in a little over a year and half achieved his first championship at the rank of [[sandanme]] 46 with a 7-0 perfect record. It would take him another two and half years of mostly winning tournaments to reach the second division [[jūryō]] in November of 2010. He entered jūryō at the same time as [[Takayasu]]. Both had the distinction of being half Filipino as well as simultaneously being the first two wrestlers to enter jūryō that were born in the [[Heisei Era]]. Masunoyama only managed a 6-9 but as he had debuted at the relatively high rank of jūryō 11, he was spared relegation. In the January 2011 tournament, he won his first five bouts in a row, but on the sixth day in morning practice he injured a ligament in his right leg. He made the decision to continue competing, and managed to beat [[Kakizoe]] on that day. However, two days later he aggravated the injury in a bout against [[Daidō Kenji|Daidō]] and was obliged to miss the next day and take a [[...|fusenpai]]. He then returned for two more days, both wins against veteran wrestlers [[Tamanoshima]] and [[Chiyohakuhō]] before losing again and re-aggravating his injury to miss the final two days. Through all this he still managed an 8-5 record with two absences. Three tournaments later (with one being missed due to the sumo [[...|match-fixing]] scandal, at the rank of jūryō 1 he came just short of a championship, but lost in a playoff to [[Myōgiryū]] who was in his jūryō debut. This record allowed Masunoyama to be promoted to the top-tier [[makuuchi]] for the following September tournament. However, on the fourth day in a bout against he would injury the same ligament in his left leg that he had previously injured in his right leg. He was forced to bow out of the tournament with only a 2-3 record, and was demoted back to jūryō. Though advised by his doctor not to enter the next tournament in order to let his injury heal, he insisted on fighting on. However, unable to do much training and hobbled by his injury he had losing records in the following two tournaments. He returned to form in the next tournament in March 2012 and posted strong winning records in this and the following tournament. He re-entered makuuchi in July of 2012, marking it with an 11-4 win and the [[Sanshō (sumo)|Fighting Spirit]] prize. Since then, however, he has had two losing tournaments to only one winning one and it remains to be seen whether he will remain a makuuchi regular.