The two heavyweights of women’s hockey square off in what could be a preview of the 2018 Winter Olympics gold medal game Thursday.  Team U-S-A plays Team Canada in a preliminary round showdown.  Both squads are 2-0 so far.  Canada is going for its fifth straight Olympic gold medal in the South Korean games.  It scored twice to come from behind at Sochi four years ago.  Of the four straight victories by the Canadians, three of them came at the expense of Team U-S-A.  Several former Badgers play for both of the teams.