On December 6, 1971, he teamed with Rene Goulet to win the WWWF World Tag Team Championship from the inaugural champions, Luke Graham and Tarzan Tyler, in two straight falls of a best-two-out-of-three-falls match in Madison Square Garden. They lost the championship on February 1, 1972, to Baron Mikel Scicluna and King Curtis. During the 1960s, Gotch began wrestling in other countries. He wrestled in Australia as Karl Krauser, and in 1965 he defeated Spiros Arion to win the International Wrestling Alliance's Heavyweight Championship. He had also begun working in Japan, where he became very popular due to his amateur wrestling style. He wrestled in the main event of the very first show held by New Japan Pro Wrestling (NJPW) on March 6, 1972, defeating Antonio Inoki. His final match occurred on January 1, 1982, when he pinned Yoshiaki Fujiwara with the German Suplex. Throughout the 1970s and 1980s, Gotch worked as both the booker and trainer for NJPW. He trained several wrestlers in Japan, including Hideki Suzuki, Hiro Matsuda, Satoru Sayama, Osamu Kido, Barry Darsow, Minoru Suzuki and Yoshiaki Fujiwara. Istaz was married and had a daughter. They resided in Florida. Gotch became known as "Kamisama" in Japan. Gotch's wrestling style had a big impact on Inoki, who adopted and popularized his submission-based style. Some of Istaz's trainees founded the Universal Wrestling Federation in Japan in 1984, which showcased the shoot-style of professional wrestling. The success of UWF and similar promotions influenced Japanese wrestling in subsequent decades, and changed the style of matches in NJPW and All Japan Pro Wrestling. The German suplex is named after Gotch. Gotch was inducted into the Wrestling Observer Hall of Fame as part of the inaugural class in 1996. In 2007, he was inducted into the Professional Wrestling Hall of Fame. Istaz died on July 28, 2007 in Tampa, Florida at the age of 82.