Christine Masse, a Seattle attorney who's spent her entire 25-year career with the law firm Miller Nash, is stepping down to become chief legal officer of the city's two professional soccer teams—Major League Soccer's Seattle Sounders and the National Women's Soccer League's Seattle Reign.

The two teams have had overlapping ownership since June, when the Sounders combined with private equity giant Carlyle Group to buy the Reign for $58 million from the French holding company OL Groupe.