Mauritania at the 2000 Summer Olympics

Fatou Dieng was 16 years old at the time of the Sydney Olympics, and was making her only Olympic appearance.^[6][7] She was the first female competitor ever sent to the Olympics by Mauritania.^[8] On 23 September, she took part in the first round of the women's 100 metres, and was drawn into heat seven. She finished the race in 13.69 seconds, ninth and last in her heat, and over two seconds behind the heat's winner, Chandra Sturrup of the Bahamas.^[9] In the event overall, the gold medal is vacant due to original gold medalist Marion Jones of the United States admitting to steroid use and forfeiting her medals and results from the Sydney Games.^[10][11] Officially, the medals in the event are held by Ekaterini Thanou of Greece and Tayna Lawrence (the original bronze medalist) of Jamaica sharing silver, and Merlene Ottey, also of Jamaica, the original fourth-place finisher, being awarded a bronze.^[11] Gold was left vacant because Thanou, the original silver medalist, had her own issue with missing a drug test at the 2004 Summer Olympics^[11][12]

Sidi Mohamed Ould Bidjel was 18 years old at the time of these Games, and was likewise making his only Olympic appearance.^[13][14] On 25 September, he participated in the first round of the men's 1500 metres, and was assigned the third heat. He finished his race in a time of 4 minutes and 3.74 seconds, 14th and last in his heat, and he was eliminated.^[15] The gold medal was eventually won in Olympic-record time of 3 minutes and 32.07 seconds by Noah Ngeny of Kenya, the silver medal was earned by Hicham El Guerrouj of Morocco, and the bronze medal was taken by fellow Kenyan Bernard Lagat.^[16][17]

• Mauritania at the 2000 Summer Paralympics