It was the second consecutive road win for the 6-2 Rush, which rallied from a 14-point deficit to take a one-point lead over the Cleveland Gladiators early in the fourth quarter.
First a Gould field goal snapped a tie at 42. After Cleveland scored the go-ahead touchdown with just seconds to play, Martin stunned Cleveland with a kickoff return for a game-winning touchdown.
The Rush edged Cleveland last month on a Gould field goal in its home opener at Allstate Arena.
The Rush returns home Friday night and will host the Jacksonville Sharks, who took a 6-1 record into its game against Spokane late Saturday night.