Bellator 300: Nurmagomedov vs. Primus was a mixed martial arts event produced by Bellator MMA, that took place on October 7, 2023, at the Pechanga Arena in San Diego, California, United States. A Bellator Lightweight World Grand Prix semifinal bout for the Bellator Lightweight World Championship between current champion Usman Nurmagomedov and former champion Brent Primus was the main event.