On August 31, 1992, he was dealt to the Texas Rangers by the Oakland Athletics in exchange for Jeff Russell, Ruben Sierra, Bobby Witt, and cash. On September 9, 1994, he was dealt by the Texas Rangers to the Boston Red Sox in exchange for Otis Nixon and Luis Ortiz. He was given free agency on October 30, 1995. He signed with the Seattle Mariners on December 14, 1995. Canseco began his major league career with the A's in 1992 at the age of 24. That year, he played in 80 games and hit.289 with 26 homers and 83 RBI's. In 1993, his role increased as he played in 137 games and finished with a.294 average, 32 homers, and 99 RBI's. In 1994, his final season with the A's, he played in only 42 games due to injuries but still managed to hit.333 with 12 homers and 38 RBI's. He was then traded to the Rangers where he finished out the season with them. In 95 games with the Rangers, Canseco hit.273 with 13 homers and 49 RBI's. He also played two games for the California Angels that season without getting any hits. The Red Sox acquired him before the start of the 1995 season and he spent most of the year with them. In 46 games with them, Canseko hit.272 with six homers and 22 RBI's. After the season was over, he signed with the Mariners.