On 10 September 2006, he made his Ligue 1 debut in a match against Toulouse FC replacing Monsef Zerka in the 68th minute.

18 days later, he scored on his international debut in a 3–1 return leg win against tournament favourites FC Schalke 04 in the first round of the UEFA Cup; he was involved in all three goals.

In his first spell at AS Nancy, he made a total of 115 league appearances scoring 13 goals with 8 of those coming in his last season at the club.

On 21 July 2010, Fenerbahçe announced that Dia had joined the team on a four-year contract for a sum of €8 million.

[2] He ended a long scoring drought on 5 February 2011 with a goal against Manisaspor, as Fenerbahçe won 3–1 in the dying minutes of the game.