Semedo was loaned again for the 2006–07 campaign, moving to Serie A's Cagliari Calcio. He made his club debut in the Coppa Italia, but would only appear three times in the league, the first as a late substitute in a 1–3 away loss against A.C. Milan on 21 April 2007. He was sent off in his last match, a 1–2 defeat at Ascoli Calcio 1898, with the Sardinians barely avoiding relegation.