Two high-profile signings make their promotional debuts Friday at Bellator 191. In the main event, former UFC interim bantamweight title challenger Michael McDonald fights for the first time in 2017 when he meets Peter Ligier in a 135-pound contest. In the co-headliner, former UFC women’s strawweight title challenger Valerie Letourneau also makes her 2017 debut in a flyweight bout against Kate Jackson . McDonald and Letourneau could insert themselves in the title pictures of their divisions with dominant victories.