|Full name||Iomar do Nascimento|
|Date of birth||8 April 1966|
|Place of birth||Santa Rita, Paraíba, Brazil|
|Height||1.76 m (5 ft 9 1⁄2 in)|
|Playing position||Defensive midfielder|
|1983–1985||Santa Cruz (PB)||?||(?)|
|1985–1990||Vasco da Gama||79||(7)|
* Senior club appearances and goals counted for the domestic league only.
Mazinho played 35 internationals for Brazil, winning the 1989 Copa América, 1994 World Cup, and a Silver medal at the 1988 Olympics. He was also named in the squads for the 1990 World Cup and the 1991 Copa América.
Mazinho played with Vasco da Gama, Palmeiras and Vitória in his homeland, with Lecce and Fiorentina in Italy, and with Valencia, Celta Vigo and Elche in Spain. Starting his career as left back, he moved to the midfield in the early nineties.
He had 35 caps with the Brazilian national team with the first one coming in May 1989 in a friendly against Peru and the last one during the 1994 World Cup. His main achievement was winning the 1994 World Cup where he was the third member of the three men and baby celebration with Bebeto and Romário in the quarter-final win against the Netherlands. Mazinho was also a Copa América winner in 1989 at which point he was playing as a full-back for Brazil.
Another player nicknamed "Mazinho", real name Waldemar Aureliano de Oliveira Filho, played for Brazil alongside the preceding player at 1991 Copa América. He was known as "Mazinho Oliveira" or "Mazinho II" to avoid confusion.
In January 2009 he was appointed as a new head coach of the Greek side Aris Thessaloniki replacing Spanish Enrique Hernández. He was replaced with former Valencia coach Héctor Cúper in November 2009.
- FIFA World Cup in 1994 with the Brazilian national team
- Copa America in 1989 with the Brazilian national team
- Campeonato Carioca (Rio de Janeiro State championship) in 1987 and 1988 with Vasco da Gama
- Campeonato Brasileiro (Brazilian championship) in 1989 with Vasco da Gama, in 1993 and 1994 with Palmeiras
- Taça Guanabara in 1987 and 1990 with Vasco da Gama
- Campeonato Paulista (São Paulo State championship) in 1993 and 1994 with Palmeiras
- Rio – São Paulo Tournament in 1993 with Palmeiras
- "Brazil - Record International Players". rsssfbrasil.com. Retrieved 1 October 2011.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
- "Mazinho". sambafoot.com. Retrieved 1 October 2011.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
- "Mazinho sustituye a Quique Hernández como entrenador del Aris de Salónica" (in Spanish). AS.com. 22 January 2009. Retrieved 22 January 2009. <templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
- "South American Team of the Year". 16 January 2009. Retrieved 30 October 2015.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>