Junichi Tazawa is a Japanese professional baseball pitcher for ENEOS of the Japanese Industrial League. He has played in Major League Baseball (MLB) for the Boston Red Sox, Miami Marlins and Los Angeles Angels. He also played in the Chinese Professional Baseball League (CPBL) for the Wei Chuan Dragons.

The posting system is a baseball player transfer system that operates between Nippon Professional Baseball (NPB) and Major League Baseball (MLB). Despite the drafting of the United States – Japanese Player Contract Agreement, unveiled in 1967 to regulate NPB players moving to MLB, problems began to arise in the late 1990s. Some NPB teams lost star players without compensation, an issue highlighted when NPB stars Hideo Nomo and Alfonso Soriano left to play in MLB after using loopholes to void their existing contracts. A further problem was that NPB players had very little negotiating power if their teams decided to deal them to MLB, as when pitcher Hideki Irabu was traded to an MLB team for which he had no desire to play. In 1998, the Agreement was rewritten to address both problems; the result was dubbed the "posting system".