Tsubakihara for the fourth time in his career at Krush 96 on December 16, 2018. Tsubakihara had won their sole professional meeting by majority decision. Gunji won the closely contested bout by split decision, after an extra round was fought. Gunji met the undefeated Masashi Kumura in the tournament finals, held at Krush 98 on February 16, 2019. Kumura won the fight by unanimous decision, with scores of 30-29, 30-29 and 30-28. Gunji suffered a broken jaw during the bout, which forced him out of competition for the next ten months. Second title run Gunji was scheduled to fight Masashi's brother Shuhei Kumura in the co-main event of Krush 106 on October 13, 2019. Gunji won the fight by unanimous decision. Gunji faced Suriyanlek Aor.Bor.Tor. Kampee in the co-main event of Krush 111 on February 24, 2020. He won the fight by unanimous decision, scoring a single knockdown in the third round. His two fight winning streak earned Gunji the right to challenge the reigning Krush Super bantamweight champion Masashi Kumura, at Krush 117 on September 26, 2020. They previously fought at Krush 98, with Kumura winning by unanimous decision. Kumura won the rematch by unanimous decision, scoring a single knockdown in the third round with a well placed knee to the head of Gunji, as the latter was ducking out of an exchange. He was ranked in the Combat Press flyweight (-56.7 kg) top ten between September 2020, when he peaked at #5, until March 2021, when he moved up in weight. Combat Press previously ranked him in their strawweight top ten between May and December 2019, peaking at #6 in May and June. Featherweight career Early featherweight career Following his second failed title bid, Gunji moved up from super bantamweight (-55 kg) to featherweight (-57.5 kg). He was scheduled to make his divisional debut against Yusho Kamemoto at K-1 World GP 2020 Winter's Crucial Bout on December 13, 2020. Gunji won the fight by a second-round knockout. He scored the first knockdown of the fight at the 1:32 minute mark of the second round, dropping his opponent with a right straight-left hook combination. Although Kamemoto was able to beat the eight-count, he was quickly knocked down again with a left hook, prompting the referee to stop the fight. Gunji was scheduled to face Riku Morisaka in a rematch at K-1: K'Festa 4 Day 1 on March 21, 2021.