After starting out at Casa Pia, Semedo amassed Primeira Liga totals of 97 games and 11 goals over the course of three seasons with Estrela Amadora, where he played six years overall.
He also competed professionally for CFR Cluj, Steaua București and Unirea Urziceni in Romania, Alki Larnaca in Cyprus, and Khazar Lankaran in Azerbaijan.
[1][2] In 2000, he went to play for Estrela Amadora, making his Primeira Liga debut on 20 August when coach Quinito sent him in the 59th minute in order to replace Jorge Cadete in a 2–0 away loss with Leiria.
[1][2][7] He made his Liga I debut on 30 July 2006 when player-coach Dorinel Munteanu sent him on the field in the 63rd minute in order to replace Romeo Surdu in a 3–1 away victory over Oțelul Galați.
[1][14] In 2008, Semedo was transferred by Steaua București from CFR for 1.2 million€, being presented at a press conference alongside George Ogăraru, Ricardo Pedriel and Andrei Ionescu.
[15] On 13 September, Semedo scored from a corner kick on his debut, as coach Marius Lăcătuș used him as a starter in Steaua's 4–1 win against Farul Constanța.
[1][2][27] In the summer of 2011, Semedo penned a one-year contract with Khazar Lankaran where he was wanted by Romanian coach Mircea Rednic who gave him his Azerbaijan Premier League debut on 27 August in a 1–1 with Ravan Baku.
[30] He was selected by coach Agostinho Oliveira to be part of the squad that participated at the final tournament, playing in a loss with Switzerland U21 and a victory over England U21 as they did not get past the group stage.
[33] In an interview for Orange Sport from 2022, he talked about his experiences with racism in football and how he views it:"To me it seemed perfectly normal to hear racist insults when I was playing.