Katayama was released by the Rakuten Eagles after the 2017 season. He attended the twelve-team tryouts and later accepted an offer to be a player/pitching coach for the BC League’s Musashi Heat Bears. Katayama hurt his left elbow in 2014 and at one point attempted a comeback as a position player. He signed an Ikusei contract with Rakuten for the 2016 season and decided to go back to pitching. He had surgery on his left elbow in March 2017 and was released after the season.
Katayama also divorced his wife during the 2016 season and was living out of a hotel (5,000 yen a night) when he signed with Musashi.