The1973American League Championship Series was a semifinal matchup inMajor League Baseball's1973 postseason which took place between October 6 and 11, 1973. TheOakland Athletics defeated theBaltimore Orioles, three games to two. Games 1 and 2 were played inMemorial Stadium in Baltimore; Games 3–5 were played at theOakland Coliseum. It was the second match-up between the two teams in the ALCS.

Oakland won the series, 3–2.

In Game 1,Jim Palmer spent 16 minutes retiring the side in the top of the first inning. He walked the first two batters and struck out the next three. The Orioles went to work against leftyVida Blue and his successor,Horacio Piña in the bottom half.Merv Rettenmund singled andPaul Blair walked beforeTommy Davis's RBI double put the Orioles up 1–0.Don Baylor then walked and one out later,Earl Williams's two-run single knocked Pina out of the game.Andy Etchebarren was hit by a pitch to load the bases andMark Belanger's RBI single made it 4–0 Orioles. They added to their lead on Etchebarren's RBI single in the seventh and Baylor's RBI single in the eighth, both with two on offBlue Moon Odom. It was more than they needed as Palmer pitched a five-hit shutout, striking out 12 Athletics along the way.

The Orioles' ALCS winning streak was snapped at 10 in Game 2.Bert Campaneris led off the game with a home run offDave McNally, but the Orioles tied the game in the bottom of the first whenAl Bumbry drew to leadoff walk, moved to third on a single and scored onTommy Davis's groundout. Back-to-back home runs leading off the sixth byJoe Rudi andSal Bando off McNally put the Athletics up 3–1. In the bottom half, the Orioles got back-to-back leadoff singles beforeEarl Williams's one-out RBI double cut Oakland's lead to 3–2. Bando's second home run of the game in the eighth off McNally padded Oakland's lead to 5–2. The Orioles hit two singles in the bottom half offCatfish Hunter, who was relieved byRollie Fingers andBrooks Robinson's RBI single made it 5–3 Oakland, but they got that run back in the ninth whenAngel Mangual hit a leadoff single offBob Reynolds, moved to third on a sacrifice bunt and passed ball, and scored on Campaneris's single. Hunter, who served up so many during the season that he threatened an A.L. record, allowed none as the Athletics evened the series as the two teams headed to Oakland for Game 3.

The third game, postponed a day by inclement weather—the postponement trigged a rhubarb between American League PresidentJoe Cronin and Athletics PresidentCharlie Finley—was played at Oakland and produced a brilliant pitching battle between a pair of southpaws,Mike Cuellar of Baltimore andKen Holtzman. Up to that point, Cuellar had allowed only three hits. he had a one-hit shutout for the first seven innings as he carefully nursed a 1–0 lead given him by Earl Williams' homer in the second inning. But in the eighth, pinch-hitterJesús Alou singled and pinch-runnerAllan Lewis was sacrificed to second byMike Andrews. The play was controversial in that Cuellar appeared to have a force out at second base, but he ignored catcher Etchebarren's yells and took the safe out at first. This proved costly as, one out later,Joe Rudi singled home Lewis to tie the score.Bert Campaneris, first man up in the 11th, snapped a 1–1 tie by hitting Cuellar's second pitch over the left-field fence for a home run.

In Game 4, the Athletics knocked outJim Palmer with a three-run outburst in the second inning. After a leadoff double and subsequent single,Ray Fosse's double scored two andDick Green's double scored another. The Athletics made it 4–0 in the sixth on Fosse's bases-loaded sacrifice fly offBob Reynolds.Vida Blue pitched six shutout innings before falling apart in the seventh.Earl Williams drew a base on balls with one out andDon Baylor followed with a single.Brooks Robinson came through with a run-producing single and Andy Etchebarren hit the next pitch for a home run, making the score 4–4. The next inning,Bobby Grich hit a home run offRollie Fingers and that, coupled withGrant Jackson's stout relief pitching, gave the game to the Orioles.

A surprisingly small crowd of 24,265 showed up for the final game and they sawCatfish Hunter pitch a five-hit shutout, winning 3–0. The Athletics first run in the game come in the third inning whenRay Fosse reached first on an error by third basemanBrooks Robinson, moved to second on a sacrifice bunt, and scored on a single byJoe Rudi. Right-handerDoyle Alexander lasted only until the fourth inning. In that frame he was the victim of a single byGene Tenace, who scored on a triple byVic Davalillo beforeJesus Alou added an RBI single. He was relieved by Palmer, who shut out Oakland the rest of the way, but the Orioles were helpless against Hunter's powerful pitching as the Athletics advanced to the World Series.

Pitching dominated the 5-game set, the victorious Athletics batting only .200 while the O's hit just .211.

1973 ALCS(3–2):Oakland Athletics overBaltimore Orioles

• 1973 ALCS at Baseball-Reference.com

• American League Championship Series
• 1973 Major League Baseball season
• Oakland Athletics postseason
• Baltimore Orioles postseason
• 1973 in sports in California
• 1973 in sports in Maryland
• 1970s in Baltimore
• 1970s in Oakland, California
• October 1973 sports events in the United States

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