Cuellar hurled a no-hitter for Cuban dictator Fulgencio Batista’s Army team in 1955, at age 18. Allowed to sign with the Havana Sugar Kings of the International League two years later, he struck out seven straight batters in his very first game and had a 2.44 ERA.
Cuellar bounced from team to team in the high minors before he earned a promotion to the Cardinals and helped them win the 1964 pennant. He was on the World Series roster but did not get into a game. Back in the minors, Cuellar perfected a devastating palmball and was 9-1, 2.51 when dealt to Houston. In 1966, his first full year in the major leagues, Cuellar finished second in NL ERA, behind Sandy Koufax. He won a then-club-record 16 games in 1967, fanning 203. After the 1968 season, the Astros swapped Cuellar to Baltimore for Curt Blefary, at that point a highly regarded young power hitter.
Cuellar tied Denny McLain for AL Cy Young honors with a 23-11, 2.38 performance, then in the World Series was the only Oriole to beat the Mets. He led the AL with 24 wins and 21 complete games in 1970, capping the year by hitting a wind-blown grand slam off Jim Perry in the LCS against the Twins. Cuellar was 20-9 in 1971, as four Oriole starters won at least 20 that year. After winning 18 games in both 1972 and 1973, Cuellar enjoyed his last great season in 1974: 22-10, with a league-leading .688 winning percentage. At age 42 in 1979, two years after finishing up in the majors, Cuellar attempted a comeback, compiling a 7-6 record with three clubs in the Inter-American and Mexican Leagues.
