Omar Luna had two hits, giving him 142 this season to break the team's single-season record, previously held by Gabriel Martinez (2008).
Mike Sheridan had two RBIs, while Shawn O'Malley and Mikie Mahtook each scored twice for Montgomery. Kyeong Kang walked to lead off the third inning before Thomas hit a blast over the left-field wall. Kang's two-out bloop single brought in the final run in the third.
The Biscuits, with Jacksonville's 7-3 loss at Jackson, have a one-game lead in the division with four games remaining.