Bandejas (13-3) is coming off two straight knockout victories, defeating Frans Mlambo and Ahmet Kayretli. He made a name for himself in 2018 when he knocked out the touted James Gallagher in the first round.
Pettis (19-5), meanwhile, beat Alfred Khashakyan by first-round guillotine at Bellator 238 in his first fight with the organization. He had previously fought under the UFC umbrella, going 9-5.
Other fights will include Aaron Pico vs. Solo Hatley Jr. and Jordan Mein vs. Jason Jackson. A bantamweight title fight between Juan Archuleta and Patrick Mix had originally been on the card but had to be canceled after Archuleta withdrew.
Pico is 5-3 in his career, losing by knockout in the second round at Bellator 238 versus Daniel Carey. Hatley (8-2) defeated Gaston Bolanos at Bellator 239.
Mein last fought in 2018, defeating Alex Moreno in a UFC on Fox card. He is 31-12 in his career. He'll take on Jackson, who is 11-4 and fresh off a unanimous-decision win over Kiichi Kunimoto at Bellator 236.
Bellator, which has been shut down since its Feb. 22 event in Dublin because of the COVID-19 pandemic, is also planning events for Aug. 7, Aug. 21 and Sept. 11 at the Mohegan Sun in Uncasville, Connecticut, per Helwani. The last three dates are not finalized, however.