 Complete the following phrase:  Beginning with her first Olympic win in 2008, Fraser-Pryce had been at the forefront of a booming sprint rivalry between Jamaica and the United States. At the Beijing Olympics, Jamaica captured five of a possible six gold medals in the sprints, with Fraser-Pryce and Campbell-Brown winning the 100 m and 200 m respectively, and Usain Bolt dominating the mens 100 m, 