In nine appearances with the Melbourne Aces of the Australian Baseball League during the 2010-11 winter season, Nishikawa went 2-0 with a 3.05 ERA, fifth-best in the ABL. Fanned 35 hitters in 38.1 innings while walking just 12. Spent the past two summer seasons with the Kobe 9 Cruise of Japan’s Kansai Independent League. In 2010, Nishikawa was second in the league with a 2.19 ERA, tied for the league lead with 10 wins, and third with 84 strikeouts. From 2006 to 2008, he pitched for the Kochi Fighting Dogs of the Shikoku-Kyûshû Island League.