|Full name||Sérgio Miguel Relvas de Oliveira|
|Date of birth||2 June 1992|
|Place of birth||Paços de Brandão, Portugal|
|Height||1.81 m (5 ft 11 1⁄2 in)|
|Playing position||Attacking midfielder|
|2007–2008||→ Padroense (loan)|
|2010–2011||→ Beira-Mar (loan)||6||(0)|
|2011||→ Mechelen (loan)||6||(1)|
|2012||→ Penafiel (loan)||12||(2)|
|2013–2015||→ Paços Ferreira (loan)||56||(4)|
* Senior club appearances and goals counted for the domestic league only and correct as of 00:00, 24 May 2015 (UTC).
Born in Paços de Brandão, Santa Maria da Feira, Aveiro, Oliveira arrived at F.C. Porto's youth system in 2002, at the age of 10. On 17 October 2009, still a junior, he became the club's youngest ever player to appear for the first team, in a 4–0 home win against Sertanense F.C. for the season's Portuguese Cup, at the age of 17 years, four months and 15 days; during the game he assisted Hulk in one of the goals and, the following month, signed his first professional contract, running until June 2012 with a €30 million buyout clause.
For the 2010–11 campaign, Oliveira was loaned to S.C. Beira-Mar in the top division. He made his debut in the competition on 23 October 2010, playing one minute in a 1–1 away draw against F.C. Paços de Ferreira.
In the 2011 summer, still owned by Porto, Oliveira was deemed surplus to requirements by new club manager Vítor Pereira, as practically all Portuguese players, and joined Belgian club KV Mechelen. In the following transfer window, in the same predicament, he returned to his country and signed for F.C. Penafiel in the second level.
Oliveira made his debut for the Portuguese under-19 side against Hungary, scoring the first goal of the match. He was selected for the following year's UEFA European Championship in France, netting in a 2–0 group stage win against Italy, with both teams being however eliminated after the first three games.
Oliveira was the captain of the under-21 team at the 2015 European Championship in the Czech Republic. He hit the crossbar in the first half of the the final against Sweden, and was substituted as they went on to lose in a penalty shootout after a 0–0 draw in Prague.
- FC Porto wonderkid Oliveira tied down on 30-million euro release clause; PortuGOAL, 24 November 2009
- Portugal power to opening victory; UEFA.com, 18 July 2010
- "Sweden beat Portugal on penalties to win U21 title". UEFA.com. 30 June 2015. Retrieved 30 June 2015.
- Sérgio Oliveira at footballzz.co.uk
- Sérgio Oliveira profile at ForaDeJogo
- Biography at Academia de Talentos (Portuguese)
- Sérgio Oliveira profile at Soccerway