Along with the top-five, here are four honorable mentions for the Astros’ all-time greatest rivals.
The Chicago Cubs played in the National League Central with the Houston Astros for many years, with Houston having the overall better record. They miss this list, however, as they never faced off in the postseason.
The Texas Rangers and Los Angeles Angels both sit here as well, as they’ve never faced off in the postseason and neither squad has really competed for the American League West since 2015.
Look for these two rivalries to develop in years to come. I give a slight edge here to the Angels, from the recent bench-clearing that came about after the Jake Marisnick and Jonathan Lucroy incident in 2019.