Ortiz had led off with a single through the right side off Logan Ondrusek (0-2) and went to second on Mike Napoli's single.
Sizemore's hit came on a first-pitch fastball and ended the first game between the teams in six years.
The Reds tied the game with two runs against Junichi Tazawa in eighth inning.
Notable deaths of 2014 [PHOTOS]
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