During 12 seasons of playing rugby union, Stanford was remarkably successful: the team had three undefeated seasons, three one-loss seasons, and an overall record of 94 wins, 20 losses, and 3 ties for a winning percentage of .816. However, after a few years, the school began to feel the isolation of its newly adopted sport, which was not spreading as many had hoped. Students and alumni began to clamor for a return to American football to allow wider intercollegiate competition. The pressure at rival California was stronger (especially as the school had not been as successful in the Big Game as they had hoped), and in 1915 California returned to American football. As reasons for the change, the school cited rule change back to American football, the overwhelming desire of students and supporters to play American football, interest in playing other East Coast and Midwest schools, and a patriotic desire to play an "American" game. California's return to American football increased the pressure on Stanford to also change back in order to maintain the rivalry. Stanford played its 1915, 1916, and 1917 "Big Games" as rugby union against Santa Clara and California's football "Big Game" in those years was against Washington, but both schools desired to restore the old traditions. The onset of American involvement in World War I gave Stanford an out: In 1918, the Stanford campus was designated as the Students' Army Training Corps headquarters for all of California, Nevada, and Utah, and the commanding officer Sam M. Parker decreed that American football was the appropriate athletic activity to train soldiers and rugby union was dropped.