After placing third in the American League East the previous year, the Baltimore Orioles returned to the top of the division standings in 1973, finishing the regular season with a record of 97-65, eight games ahead of the runner-up Boston Red Sox. Although not quite as strong as the Baltimore club that dominated the A.L. East from 1969 to 1971, the Orioles possessed outstanding team-balance, finishing a close third in the league with 754 runs scored, while compiling a league-leading 3.07 team ERA. Designated hitter Tommy Davis was Baltimore’s top offensive performer, batting .306 and leading the team with 89 runs batted in. A.L. Rookie of the Year Al Bumbry also made significant contributions, batting .337, stealing 23 bases, and scoring 73 runs, in fewer than 400 official at-bats.
Meanwhile, Baltimore’s league-leading pitching staff included three starters that won at least 17 games. Jim Palmer earned A.L. Cy Young honors by compiling a record of 22-9, leading all league hurlers with a 2.40 ERA, throwing 296 innings, and tossing 19 complete games. Mike Cuellar posted 18 victories, while Dave McNally added another 17.
While the Orioles won their fourth A.L. East title in five years, the Oakland Athletics finished first in the West for the third straight time. The A’s posted a regular-season record of 94-48, to finish six games ahead of the up-and-coming Kansas City Royals, who featured two of the junior circuit’s best young players in centerfielder Amos Otis and first baseman John Mayberry. Otis hit 26 home runs, drove in 93 runs, scored 89 others, and batted .300. Mayberry also hit 26 homers, knocked in 100 runs, batted .278, and led the A.L. with 122 walks and a .420 on-base percentage.
Nevertheless, Oakland remained the class of the A.L. West, leading the league with 758 runs scored and placing second in the circuit with a 3.29 team ERA. The A’s starting rotation included three 20-game winners, and their deep bullpen featured one of the best closers in the game. Catfish Hunter finished 21-5 with a 3.34 ERA. Ken Holtzman compiled a record of 21-13 and led the staff with a 2.97 ERA, 16 complete games, and 297 innings pitched. Vida Blue went 20-9 with a 3.28 ERA. Meanwhile, Rollie Fingers anchored the bullpen by winning seven games, saving 22 others, and compiling an ERA of 1.91.
The trio of Sal Bando, Bill North, and Reggie Jackson led the A’s on offense. Team captain Bando hit 29 home runs, drove in 98 runs, scored 97 others, and batted .287. The speedy North batted .285, scored 98 runs, and finished second in the league with 53 stolen bases. Jackson batted .293 and topped the circuit with 32 home runs, 117 runs batted in, 99 runs scored, and a .531 slugging percentage. His outstanding performance earned him A.L. MVP honors.
The League Championship Series between Oakland and Baltimore turned out to be an extremely competitive one that went the full five games. After the teams split the first two games in Baltimore, the A’s grabbed a 2-1 Series lead when Ken Holtzman threw a complete-game three-hitter in leading Oakland to a 2-1 victory in Game Three. The Orioles, though, evened the Series again by rallying from a 4-0 deficit in the final three innings to take Game Four by a score of 5-4. A 3-0 complete-game shutout by Catfish Hunter in Game Five subsequently earned Oakland a return-trip to the World Series.
Awaiting the A’s in the Fall Classic were the New York Mets, who managed to capture the National League pennant even though they finished the regular season only three games over .500. After defeating the heavily-favored Cincinnati Reds in the NLCS, the Mets proved to be a difficult foe for Oakland as well, extending the Series to seven games. The A’s finally prevailed, winning Game Seven by a score of 5-2 on a pair of two-run homers by Bert Campaneris and Reggie Jackson. Jackson earned Series MVP honors by batting .310, collecting nine hits, and knocking in six runs.
Other notable events from around the league and players who distinguished themselves over the course of the season included:
• January 3 – A group of investors, headed by shipbuilder George Steinbrenner, purchased the New York Yankees from CBS for $10 million.
• January 18 – Orlando Cepeda signed with the Boston Red Sox, making him the first player signed by a team strictly as a designated hitter.
• February 27 – Chicago White Sox slugger Dick Allen signed a three-year contract for an estimated $250,000 per year, making him the highest-paid player in major league history.
• April 6 - At Fenway Park, Ron Blomberg of the New York Yankees became the first designated hitter in major league history. He earned a walk against Boston Red Sox pitcher Luis Tiant in his first plate appearance.
• April 10 – The Kansas City Royals opened their new park, Royals Stadium, with a 12–1 rout of the Texas Rangers. The game was attended by 39,464 fans braving 39-degree weather.
• May 15 – Nolan Ryan threw a no-hitter against the Kansas City Royals.
• July 1 – Luis Aparicio of the Boston Red Sox stole the 500th base of his career during a 9–5 loss to the Milwaukee Brewers.
• July 3 – Brothers Gaylord Perry (Indians) and Jim Perry (Tigers) pitched against each other for the only time in their careers.
• July 15 - Nolan Ryan pitched his second no-hitter of the season, striking out 17 Detroit Tigers during a 6-0 California win.
• July 20 – Chicago’s Wilbur Wood started and lost both games of a doubleheader against the New York Yankees, dropping the contests by scores of 12–2 and 7–0.
• August 1 – With the score tied at 2–2 in the top of the ninth inning at Fenway Park, an incident took place that typified the intense rivalry between the Red Sox and the Yankees, as well as the personal feud that existed between catchers Carlton Fisk and Thurman Munson. Attempting to score on Yankee teammate Gene Michael’s missed squeeze attempt, Munson barreled into Fisk at home plate. The incident triggered a 10-minute bench-clearing brawl that resulted in both catchers being ejected.
• September 3 – After 11 years at the helm (944–806 .539), Ralph Houk resigned as the New York Yankees' manager. He ended up piloting the Detroit Tigers the following season
• September 27 – Capping a memorable season, Nolan Ryan struck out 16 Minnesota Twins during a 5–4, 11-inning win for the California Angels. The final strikeout, his 383rd of the season, broke Sandy Koufax's single-season record.
• September 30 – The New York Yankees played their final game in the original Yankee Stadium, losing to the Detroit Tigers 5–2. Yankee Stadium subsequently remained closed until 1976 while undergoing major renovations.
• October 23 – Athletics owner Charlie Finley revealed that he had no intention of releasing manager Dick Williams from his contract unless he were to receive adequate compensation from the team that signed him. Williams had resigned following the World Series victory two days earlier.
• By finishing the year with a record of 24-20, Chicago’s Wilbur Wood became the first pitcher in 57 years to both win and lose 20 games in a season. Wood threw a major-league leading 359 innings.
• Baltimore’s Bobby Grich established a new major league record for second basemen by compiling a .995 fielding average.
• Detroit's John Hiller established a new major league record by saving 38 games. Hiller also posted 10 victories, compiled a 1.44 ERA, and led all A.L. pitchers with 65 mound appearances.
• Yankee pitchers Mike Kekich and Fritz Peterson announced they had swapped wives, families, houses, and dogs.
• Kansas City’s Steve Busby threw a no-hitter against Detroit on April 27.
• Jim Bibby of Texas hurled a no-hitter against Oakland on July 20.
• Rod Carew led the American League with a .350 batting average, 203 hits, and 11 triples.
• The Hall of Fame inducted Warren Spahn, Billy Evans, George Kelly, Mickey Welch, Monte Irvin, and Roberto Clemente.
• Hall of Famers George Sisler, Frankie Frisch, and Chick Hafey all passed away.
• Luis Aparicio retired with the major league record for most career games at shortstop (2,581).
• California's Frank Robinson homered in a record 32nd major league park in use during his career.
• California pitchers Nolan Ryan and Bill Singer struck out 624 batters between them, establishing in the process a post-1893 major league record for two teammates.
• Boston's Tommy Harper led the American League with 54 steals.
• Cleveland's Gaylord Perry led the league with 29 complete games.
- 1973 ALCS, 1973 World Series, Al Bumbry, American League, Amos Otis, Baltimore Orioles, Bert Campaneris, Bill Singer, Billy North, Bobby Grich, Carlton Fisk, Catfish Hunter, Charles Finley, Dave McNally, Dick Allen, Dick Williams, Frank Robinson, Fritz Peterson, Gaylord Perry, Gene Michael, George Steinbrenner, Jim Bibby, Jim Palmer, Jim Perry, John Hiller, John Mayberry, Ken Holtzman, Luis Aparicio, Luis Tiant, Mike Cuellar, Mike Kekich, Nolan Ryan, Oakland Athletics, Orlando Cepeda, Ralph Houk, Reggie Jackson, Rod Carew, Rollie Fingers, Ron Blomberg, Sal Bando, Steve Busby, Thurman Munson, Tommy Davis, Tommy Harper, Vida Blue, Wilbur Wood