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The 1984 Oakland Athletics' 20-game winning streak was the longest in American League history and the second-longest in Major League Baseball history. The A's started the streak on August 14, 1984, with a 3-2 win over the Seattle Mariners at Oakland–Alameda County Coliseum. The streak ended on September 1, 1984, with a 4-3 loss to the California Angels at Anaheim Stadium.