No. 2020.01.09 · Modern Era
Arozarena to Tampa
St. Louis traded Randy Arozarena and José Martínez for Matthew Liberatore and other pieces. That October Arozarena hit ten home runs in the postseason, a record, on the way to the World Series.
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Randy Arozarena with the Rays, September 8, 2020, his first season after the trade. Not the transaction itself.
All-Pro Reels from District of Columbia, USA / CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)
January 9, 2020. The Cardinals traded Randy Arozarena and José Martínez to the Rays. The pitching prospect coming back was Matthew Liberatore, with other pieces in the deal. Arozarena was an outfielder who had reached the majors the year before and had not yet had a season of his own.
Ten months later he hit ten home runs in one postseason, a record, during Tampa Bay's run to the World Series. In 2021 he was the American League Rookie of the Year. He was an All-Star after that. Liberatore's career is not the career the ten home runs made the trade look like on a replay.
The entry is the gap between a January transaction and an October record. Arozarena was not that hitter on the day St. Louis moved him. He was that hitter before the year was over.