The game never got started and was called after a wait of nearly 2½ hours.
No makeup date was announced. This was the last day the Giants were scheduled to be in Cincinnati this season. The Reds visit San Francisco later this month.
The teams are both off Aug. 29 -- it would be the first day after the Reds finish a stretch of 20 games in 20 days and the last before they play 13 games in 13 days. Major League Baseball rules prohibit teams from playing more than 20 straight days without permission from the players union.
The Reds would be in the middle of a road trip to St. Louis and Colorado. The Giants would be in the middle of a trip to Colorado and Arizona.