Then as now, high-range shortstops were in high demand and Luis Alvarado was a standout fielder during his 9-year major league career. A native of Puerto Rico, he started professionally at age 18 in 1967 with Waterloo of the Midwest League, and played in the minors for Pittsfield and Louisville along with a few games with the Red Sox prior to joining Boston for good during the 1970 season, hitting .224 in 59 games. .
On December 1 1970 Luis Alvarado and Red Sox second baseman Mike Andrews were traded to the White Sox for aging veteran Luis Aparicio. At Chicago Luis Alvarado took over the starting shortstop job and was among the leaders in fielding percentage during his 3-year stay in Chicago. He later played for four different major league teams.