They helped the U.S. beat Argentina 2-1 in the Red Group after splitting the singles on Tuesday. Sweden defeated the Czech Republic 3-0 and led the Red Group with five wins.
The Americans have four wins in six matches, and the winner of each group will meet in Saturday's final.
Simon Bolelli won two matches, helping Italy beat Germany 2-1 in the Blue Group.
Also in the Blue Group, Spain defeated Russia 2-1.