Unusually for a sports rivalry, it arises more from circumstances surrounding the history of baseball in the two cities, about apart yet considered different markets, than anything that has so far happened on the field between the teams. Washington's previous team, the Senators, had been AL regulars for most of the 20th century, but after their 1933 pennant often finished last or almost last in the standings. Within a decade of the AL St. Louis Browns' move to Baltimore to become the Orioles in the 1950s, the Orioles became pennant contenders while the Senators moved to Minnesota and became the Twins. A replacement Senators franchise fared little better either commercially or athletically, moving to Arlington, Texas and becoming the Texas Rangers within another decade. Following that move, Orioles' owner Peter Angelos strongly opposed any attempt by Major League Baseball (MLB) to expand to Washington despite that city's larger market, arguing that both teams would suffer commercially and that the Orioles' protected market had legally expanded to Washington once the second Senators franchise moved.