Police say an anonymous caller issued the threat in a 911 call around 8 p.m. Tuesday as the Tigers were hosting the Los Angeles Angels in front of 34,000 fans.
No announcement was made, nor was there a call for an evacuation as police searched the ballpark for an explosive device.
Detroit police Sgt. Eren Stephens says no device was found.
The threat followed two similar incidents in less than a week that shut down a tunnel and a bridge connecting Detroit and Windsor, Ontario, for hours.