Bellator officials confirmed the news to MMAFighting.com Monday evening. The nature of Bronzoulis' injury was undisclosed.
While "multiple fighters" were considered for Guillard's replacement opponent, it is Campos (15-6) who will officially square off with "The Young Assassin" in the Lone Star State.
Similarly, Guillard (32-15-2, two no-contests) has dropped his last two bouts, albeit in much closer fashion.
The 32-year-old UFC and World Series of Fighting (WSOF) veteran lost a split decision to WSOF lightweight champion Justin Gaethje in November 2014, then fell to Girtz in his Bellator debut at Bellator 141, again via split decision.