A geographic rivalry with the cross-Bay American League Athletics greatly increased with the 1989 World Series , nicknamed the " Battle of the Bay " , which Oakland swept ( and which was interrupted by the Loma Prieta earthquake moments before the scheduled start of Game 3 in San Francisco ) . In addition , the introduction of interleague play in 1997 has pitted the two teams against each other for usually six games every season since 1997 , three in each city ( but only four in 2013 , two in each city ) . Before 1997 , they played each other only in Cactus League spring training . Their interleague play wins and losses ( 63 – 57 in favor of the A 's ) have been fairly evenly divided despite differences in league , style of play , stadium , payroll , fan base stereotypes , media coverage and World Series records , all of which have heightened the rivalry in recent years . The intensity of the rivalry and how it is understood varies among Bay Area fans . A 's fans generally view the Giants as a hated rival , while Giants fans generally view the A 's as a friendly rival much lower on the scale . This is most likely due to the A 's lack of a historical rival , while the Giants have their heated rivalry with the Dodgers . Some Bay Area fans are fans of both teams . The " split hats " that feature the logos of both teams best embodies the shared fan base . Other Bay Area fans view the competition between the two teams as a " friendly rivalry " , with little actual hatred compared to similar ones such as the Subway Series ( New York Mets vs. New York Yankees ) , the Red Line Series ( Chicago Cubs vs. Chicago White Sox ) and the Freeway Series ( Los Angeles Dodgers vs. Los Angeles Angels of Anaheim )
Loma Prieta earthquake
1989 Loma Prieta earthquake
San Francisco Giants