Thiebaut’s professional career started at Lebbeke. Thiebaut was then signed by Eendracht Aalst in Summer 1998, a team that played in the First Division. After showing some great displays, he moved to Cypriot team Omonia Nicosia, and returned to Belgium after that.
In Belgium he played for Dender, which was known as FC Denderleeuw at that time. Here, he showed his goalscoring capabilities. In the 2002–2003 season at Denderleeuw, Thiebaut was top-scorer in the Belgian Second Division.
His great scoring earned him another adventure. In Germany he was signed by 1. FC Saarbrücken. He played some good seasons, but decided to find his way back to Belgium in 2005. S.V. Zulte Waregem was his new team in the 2006–2007 season. Thiebaut also became top scorer with 21 goals this season, the same number of goals as Gabriel Persa who played for Dessel Sport and Fraizer Campbell playing for Royal Antwerp on loan from Manchester United.
After that, he moved to Dender and finally to MVV, another adventure abroad, this time in the Netherlands. In Maastricht he scored in his first game for MVV two times. The first goal, in the third minute, was the first goal in the season. In December 2007 was chosen footballer of the year in Eerste divisie, he was nominated as the best player in Netherlands Limburg in 2007. At MVV he scored 42 goals in 2 seasons.