He spent most of his club career in France with Le Havre and Lille, and in the UAE Pro League with Sharjah and Al-Nasr.

In 2008 he was sold to Le Havre AC,[2] with whom he played his first game in Ligue 1 on 13 May 2009 against AS Saint-Étienne, as a late substitute for Maxime Baca in a 4–2 home loss.

He joined for a €3 million fee – the club was in a good financial place after the sale of Eden Hazard to Chelsea – and his monthly salary rose from €7,000 to €120,000.

[9][14] Remaining in the United Arab Emirates, Mendes moved to Al-Nasr SC in Dubai on a two-year contract in July 2020.

[21][22][23][24] Mendes scored the decider on 10 September 2014 as Cape Verde won 2–1 against Zambia in Praia, in 2015 Africa Cup of Nations qualification.

[27] A year later, he was called up for the 2021 Africa Cup of Nations in Cameroon[28] and appeared in two of Cape Verde's matches at the tournament.

[29] In December 2023, Mendes was named in Cape Verde's squad for his fourth Africa Cup of Nations – the 2023 tournament in the Ivory Coast.