MuseumOfHoaxes.com rates the best April Fool's pranks ever:

#2: Sidd Finch
1985: Sports Illustrated published a story about a new rookie pitcher who planned to play for the Mets. His name was Sidd Finch, and he could reportedly throw a baseball at 168 mph with pinpoint accuracy. This was 65 mph faster than the previous record. Surprisingly, Sidd Finch had never even played the game before. Instead, he had mastered the "art of the pitch" in a Tibetan monastery under the guidance of the "great poet-saint Lama Milaraspa." Mets fans celebrated their teams' amazing luck at having found such a gifted player, and Sports Illustrated was flooded with requests for more information. In reality this legendary player only existed in the imagination of the author of the article, George Plimpton.

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