Michael Colla and two relievers combined on a five-hitter in the Biscuits' 3-0 win at Chattanooga on Tuesday.
Colla (3-0) gave up four hits over seven innings. He walked two, struck out four and recorded 12 groundball outs. Marquis Fleming and C.J. Riefenhauser worked an inning each. Riefenhauser picked up his 11th save.
It was Montgomery's seventh shutout this season and the fourth suffered by the Lookouts.
The Biscuits took the lead in the fifth inning. Cameron Seitzer drew a leadoff walk and scored on a double play.
In the eighth, Riccio Torrez hit a leadoff double and scored on Robi Estrada's two-out single. In the ninth, Hector Guevara walked and came home on a Seitzer single.