Since 2013
Astros vs. Rangers
The Lone Star Series
The Astros-Rangers rivalry, known as the Lone Star Series, is Major League Baseball's premier intra-state rivalry. While the teams played interleague games for years, the rivalry intensified dramatically when Houston moved to the American League West in 2013, placing both Texas franchises in the same division. The resulting twice-yearly series have become the most anticipated dates on both teams' calendars.