Wakakirin achieved ten wins in his top division debut, a feat that normally wins the Fighting Spirit Award, but he missed out, the prize going to Baruto instead. He was promoted to what was to be his highest rank of "maegashira" 9 for the January 2008 tournament, but disappointing scores of 4-11 there and 6-9 in March meant he was demoted back to the "jūryō" division. He missed out on a "kachi-koshi" winning score on the final day in May 2008, falling to 7-8. He scored 7-8 once again in July. He remained in the top half of "jūryō" after that, but did not win promotion back to the top division. He produced a good 9-6 score at jūryō 3 in January 2009 but lost to Tamawashi on the final day when a win would have virtually guaranteed a return to "makuuchi". On January 30, 2009 Wakakirin was arrested for possession of cannabis, at a CD shop in Roppongi that had been monitored by police for some time. The following day, Oguruma, his stable master, declared his intention to dismiss him as a professional sumo wrestler in the wake of the scandal and submitted his letter of resignation to Japan Sumo Association by proxy. The Sumo Association fired him on February 2, deciding on dismissal rather than the heavier penalty of expulsion that would have deprived him of a 5.3 million yen retirement bonus. This decision split the Association and was criticised by some as being too lenient. However, Wakakirin subsequently said he would not accept the severance pay. An editorial in the "Asahi Shimbun" said the newspaper was "appalled by his utter folly" in taking the drug. After being in jail for a month, Wakakirin was released on bail on February 27. He appeared at the Yokohama District Court on April 13 and pleaded guilty to cannabis possession. On April 22 he was given a ten-month prison sentence, suspended for three years. He was believed to be working for a time at his father's restaurant business. Wakakirin is the fourth wrestler to be dismissed because of cannabis use, following Wakanohō, Rohō and Hakurozan, but the first Japanese. In the same tests in September 2008 that led to Rohō and Hakurozan being dismissed, it was reported that Wakakirin's result was borderline, which put the wrestler under suspicion.