4x400m Relay:The United States won the gold medal in both the men's and women's 4x400 metres relay today in the final athletic events on the Beijing Olympic track.
In the men's race the American quartet of LaShawn Merritt, Angelo Taylor, David Neville and Jeremy Wariner clocked a combined time of two minutes 55.39 seconds.
Bahamas, represented by Andretti Bain, Michael Mathieu, Andrae Williams and Christopher Brown, finished second in 2:58.03.
The Russian team of Maksim Dyldin, Vladislav Frolov, Anton Kokorin and Denis Alexeev were third in 2:58.06.
Earlier in the women's race Sanya Richards surged past her Russian rival in the final few metres to secure the the gold medal for the US.
Richards teamed up with Mary Wineberg, Allyson Felix and Monique Henderson to win in a time of three minutes 18.54 seconds.
Russia finished second in 3:18.82 after Anastasia Kapachinskaya started the last leg with a handy lead over Richards.
Jamaica won the bronze medal in 3:20.40.