On March 8, Goto and Shibata once again faced off in the second round of the 2015 New Japan Cup in a match, where Goto was victorious. Goto eventually made it to the finals of the tournament on March 15, where he was defeated by Kota Ibushi. On May 3 at Wrestling Dontaku 2015, Goto defeated Shinsuke Nakamura to win the IWGP Intercontinental Championship for the second time. Goto made his first title defense on July 5 at Dominion 7.5 in Osaka-jo Hall, defeating Nakamura in a rematch. From July 23 to August 15, Goto took part in the 2015 G1 Climax. After six victories, one of which came over reigning IWGP Heavyweight Champion Kazuchika Okada, Goto entered the final day with a chance to advance from his block, but was eliminated after suffering his third loss of the tournament against Yuji Nagata. Through NJPW's working relationship with the Ring of Honor (ROH) promotion, Goto returned to the United States on August 21, teaming with Jay Briscoe and Mark Briscoe in a six-man tag team match, where they defeated Okada, Beretta and Rocky Romero. Goto's Intercontinental Championship reign ended on September 27 at Destruction in Kobe, when he was defeated by Shinsuke Nakamura in another title rematch.