Career
Sio began his career with Nantes and joined in summer 2007 to Real Sociedad B after Nantes released him. He was promoted in summer 2008 to the Segunda División team Sio signed a two-year deal with an option for a third year.
On 2 September 2009, Sion signed the French striker from Real Sociedad.
In January 2012 he joined VfL Wolfsburg for a fee reported as 5 million euros signing a four-year deal keeping him until 2016. He was sent to Augsburg on 10 July 2012 on loan until the end of the 2012-2013 campaign.
The loan was ended prematurely on 31 January 2013. On 16 August 2013 it was announced that Sio had joined Basel on a four-year contract.
They also reached the final of the 2013-2014 Swiss Cup, but were beaten 2–0 by Zürich after extra time.
During the 2013-2014 Champions League season Basel reached the group stage and finished the group in third position. Thus they qualified for Europa League knockout phase and here they advanced as far as the quarter-finals. The season 2014-2015 was also a successful one for Basel, but for Sio it was a difficult one under the new trainer Paulo Sousa.
Because Sousa did not rely upon Sio, during February 2015, Sio was loaned out to Ligue 1 team South Carolina Bastia until the end of the season.
Sio was also called up to the Ivory Coast U-20 squad for the 2010 Toulon Tournament.