Boyer broke into the major leagues in 1955 as a utility infielder at age 18. With no minor league experience, he played a total of 124 games for the Kansas City Athletics until he was traded to the Yankees in February 1957 in a thirteen-player deal, seven players going to Kansas City and six (including pitcher Bobby Shantz) to the Yankees. He spent three seasons in the Yankee farm system until he was called up late in 1959.
The Yankee Years
Boyer became the Yankees’ regular third baseman in 1960, beating out three others (including Gil McDougald, who in spring training had announced that this, his 10th season in the majors, would be his last) for the starting job. He batted .242 with 14 home runs and 46 RBIs as the Yankees won the pennant. However, he had a humbling moment in the first game of the World Series against the Pittsburgh Pirates. Early in the game, with two runners on base and the Yankees trailing 3-1, manager Casey Stengel, never confident in Boyer's hitting, replaced him with a pinch-hitter, Dale Long, who flew out to right fielder Roberto Clemente. The Yankees didn’t score in the inning and lost 6-4, ultimately losing the Series in Game 7 on Bill Mazeroski’s home run off Ralph Terry in the bottom of the ninth. Boyer himself didn't play in the Series again until Game Six.
After the Series, the Yankees fired Stengel. Ralph Houk replaced him as manager and restored some of the confidence in Boyer that Stengel had taken away. Whereas Stengel preferred other players at third base over Boyer, Houk saw something special in Boyer's defensive prowess and gave him the opportunity to play every day.
The 1961 team (with Mickey Mantle, Roger Maris, Elston Howard, Yogi Berra and Moose Skowron), which defeated the Cincinnati Reds in the World Series, was considered by many as the best ever, with Mantle and Maris chasing Babe Ruth’s record of 60 home runs in 1927 (Maris eventually broke the record on the final day) and Whitey Ford winning 25 games and losing only four. What Boyer himself didn’t do with the bat (he hit only .224 during the regular season), he more than made up for with the glove in an infield that also featured the double play duo of shortstop Tony Kubek and second baseman Bobby Richardson.
Boyer enjoyed liquor and good times off the field, but was serious and spectacular on it. He rivaled Brooks Robinson defensively, leading American League third basemen (finishing ahead of even Robinson) in putouts, assists and double plays in all three of Houk’s seasons as manager (1961–1963)—yet Robinson, not Boyer, won the Gold Glove Award each year.
Boyer’s offensive numbers improved in 1962: career bests in batting average .272, home runs (18) and runs batted in (68). He also came within nine assists of the third base record of 405 set by Harlond Clift of the 1937 St. Louis Browns. Once again, the Yankees won the World Series, this time in seven games over the San Francisco Giants. The Series ended with Richardson catching Willie McCovey’s line drive with runners on second and third; just a few feet to either side and Richardson could not have gotten his hands on it and the Giants would have scored two runs and won the Series. In 1963 Boyer batted .251 with 12 home runs and 54 RBIs as the Yankees won another pennant; however, they were swept by the Los Angeles Dodgers—the first time the Yankees had ever been swept in a World Series. Dodger ace Sandy Koufax won the first and fourth games, striking out a series record 15 batters in the opener. Boyer was the only Yankee regular not to strike out against Koufax.
After the 1963 season Houk was promoted to general manager and Berra replaced him as field manager. Early on, the 1964 team slumped under Berra, especially Boyer who batted .218 on the season. As Berra’s managing improved, the team improved with it and won its fifth straight pennant by one game over the Chicago White Sox and two over the third-place Baltimore Orioles. The Yankees faced the St. Louis Cardinals in the World Series with Clete playing against his brother Ken. The Yankees lost in seven games, but not before Ken and Clete became the first brothers to hit home runs in a World Series game. In the 7th inning of that seventh game, Ken homered off Yankee pitcher Steve Hamilton and exchanged nods with Clete. Clete returned the favor in the 9th after homering off Cardinal ace Bob Gibson.
After the 1964 Series, Houk unceremoniously fired Berra (in mid-season the management, dissatisfied with Berra's work, made up their mind to fire him at the end of the season no matter what the Yankees did) and replaced him with Johnny Keane, who had managed the Cardinals to the World Series victory over the Yankees. The Yankees hardly responded to Keane from his first day on the job in 1965; Boyer in particular entered everyone’s doghouse by getting drunk during spring training and punching out a man in a bar in Fort Lauderdale, Florida. During the season, he did bat .251 with a career-tying 18 home runs, but the Yankees slumped to sixth place—their lowest finish in 40 years. In 1966 the Yankees fired Keane two weeks into the season, and Houk returned as manager. His second stint, however, was far less successful—the Yankees finished dead last. After a season in which he hit .240 with 14 home runs, Lee McPhail, who replaced Houk as general manager, traded Boyer to the Atlanta Braves for Bill Robinson, who was supposed to be the next Yankee superstar after being named Minor League Player of the Year. McPhail claimed Boyer’s drinking prompted the trade; his teammates insisted that the trade was the result of his independence and his outspoken nature.
In 1967 Boyer had his best offensive season ever. Plying in hitter-friendly Fulton County Stadium, he established career highs in home runs (26) and RBIs (96) in a lineup that featured the likes of Hank Aaron, Joe Torre, Felipe Alou and Mack Jones. He also continued his mastery of the glove, leading National League third baseman in fielding both in 1967 and 1969. In the latter year, he finally won the Gold Glove Award that had eluded him in his Yankee years. On August 31 of that year, he fell victim to Morganna, the famed buxom “Kissing Bandit.” Prior to the kiss, he had been mired in a 1-for-17 slump; in that very at-bat, Clete drove in a run with a single. He got two more hits later in the game, then eight more hits in his next 15 at-bats. That season the Braves won the Western Division title (both leagues now had Eastern and Western Divisions after each expanding from 10 teams to 12) but lost in the playoffs to the eventual World Champion New York Mets.
Boyer continued to sparkle at third base until he was released by the Braves on May 28, 1971, after a bitter feud with owner Paul Richards and manager Lum Harris over mismanagement. Boyer complained that the organization didn’t teach the players the proper fundamentals. Richards countered that Boyer was a troublemaker. He left Major League Baseball and resurfaced in Japan, where he played professionally from 1972 to 1975. Afterwards, Boyer returned to the Major Leagues as a third-base coach with the Yankees and the Oakland Athletics, mostly with former teammate Billy Martin as manager.
- Signed as an amateur free agent (bonus baby) by Kansas City Athletics (May 31, 1955).
- Traded by Kansas City Athletics to New York Yankees (June 4, 1957) completing trade in which New York Yankees traded Irv Noren, Milt Graff, Mickey McDermott, Tom Morgan, Rip Coleman, Billy Hunter and a player to be named later to Kansas City Athletics in exchange for Art Ditmar, Bobby Shantz, Jack McMahan, Wayne Belardi and 2 players to be named later (February 19, 1957); New York Yankees received Curt Roberts (April 4, 1957) and Kansas City Athletics received Jack Urban (April 5, 1957).
- Traded by New York Yankees to Atlanta Braves in exchange for Bill Robinson and Chi-Chi Olivo (November 29, 1966).
- Released by Atlanta Braves (June 2, 1971).