Through eight days of competition with more than 130 events determined, the United States and China each remain in a dead heat atop the leaderboard for the overall medal lead.

Both countries picked up a whopping 11 medals on Saturday alone, and are now each well more than 20 total medals ahead of the rest of the world. Along with sweeping both the 4x100m men's and women's individual medleys, Team USA also managed to walk away with a pair of golds in tennis, as Serena Williams (singles) and Mike and Bob Bryan (doubles) each snagged a gold medal.

Williams, who took the women's singles title over Russia's Maria Sharapova, needed only 63 minutes to cruise to a two-set victory (6-0, 6-1), while the Bryan brothers managed to crack France's duo of Michael Llodra and Jo-Wilfried Tsonga after a tough second set tiebreaker (6-4, 7-6 (7-2)).

Here are the leaders through eight days:

1. United States, 54 (26 gold, 13 silver, 15 bronze)

2. China, 53 (25, 16, 12)

3. Great Britain, 29 (14, 7, 8)

4. Russia, 28 (3, 15, 10)

5. Japan, 24 (2, 10, 12)

For a full medal count tracker from Sports Illustrated, go here.

Stay with this StoryStream for more coverage of local athletes at this year's games, and be sure to check out SB Nation's Olympic hub for more coverage from London.