Madu handled the third leg of the women's 4 x 100 relay as the U.S. squad won with a time of 43.89 seconds, the world junior leader for 2012. Germany finished second in 44.24 with Brazil third in 44.29.
Bailey ran the second leg of the men's 4 x 100 relay that posted a winning time of 38.67, just 0.01 off the World Junior record and championship record set by the 2004 U.S. Junior team in Grosseto, Italy. The Americans defeated Jamaica (38.97) and Japan (39.02) while Great Britain was disqualified.
It was the second medal for Bailey at these championships. He also shared the bronze medal in the 400 final.
Olivia Ekponé ran the anchor leg of the women's 4 x 400 relay during the qualifying round. The United States initially won the heat in commanding fashion with a time of 3:34.12.
However, the U.S. and Romania were disqualified for passing the baton out of their respective exchange zones. Officials had lined up the second leg runners in the wrong position, so both countries filed a protest. An option to rerun the race was offered, with the U.S. accepting and Romania denying.
The American squad will have to rerun the race on Sunday morning and needs a to better the time of 3:39.44 to make the final.