File Photo: Belgium's Guillaume Gillet (L) celebrates with team mate Dries Mertens (C) after scoring against Croatia during their 2014 World Cup qualifying soccer match in Brussels September 11, 2012 (Photo: Reuters)
Anderlecht captain Gillet, who has 20 caps for the national side, has spent the past seven seasons with the Belgian club, winning four league and one Cup title.
The 30-year-old joins compatriot Logan Bailly, who arrives in the mediterranean island side on trial following two seasons in goal at Belgian top flight side Louvain.
Bastia finished tenth in Ligue 1 last season.
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