Carl Michael Yastrzemski Sr. ( yə-STREM-skee; born August 22, 1939), nicknamed “Yaz”, is an American former professional baseball player who played his entire career with the Boston Red Sox of Major League Baseball (MLB). He started his career primarily as a left fielder, but also played 33 games as a third baseman. Later in his career, he was mainly a first baseman and designated hitter.

Yastrzemski is an 18-time All-Star, the possessor of seven Gold Gloves, a member of the 3,000 hit club, and the first American League player in that club to also accumulate over 400 home runs. He is second on the all-time list for games played, and third for total at-bats. He is the Red Sox’s all-time leader in career RBIs, runs, hits, singles, doubles, total bases, and games played, and is third on the team list for home runs, behind Ted Williams and David Ortiz. He was elected to the Baseball Hall of Fame in 1989.

In 1967 Yastrzemski achieved a peak in his career, leading the Red Sox to the American League pennant for the first time in over two decades and being voted the 1967 American League MVP. Yastrzemski also won the Triple Crown that year, something not accomplished again in the Major Leagues until Miguel Cabrera did so in 2012.