Josh Cohen scored a team-high 19 points and Saint Thomas drilled a critical 3-pointer with 18 seconds remaining to help host Southern California fight off a tenacious Idaho State 75-69 on Thursday in Los Angeles.The Trojans (2-0) led by as many as 12 and held an advantage for more than 35 minutes, and they needed every bit of that edge to hold off the Bengals.Cohen scored his final two points on a jumper with 2:25 remaining, which proved to be the difference as USC held the lead the rest of the way.Idaho State (0-2) had a chance to regain the lead in the final minute after Jake O’Neil grabbed the last of his nine rebounds with his team down 68-67. Dylan Darling, who scored a game-high 22 points, missed a go-ahead attempt with 48 seconds remaining.On the ensuing possession, Cohen found Thomas for a 3-pointer that snuffed out any hope of an Idaho State upset. The loss marked the Bengals’ second down-to-the-wire defeat against a power-conference opponent after they took Arizona State to the brink on Tuesday.Thomas was one of three Trojans in double-figures with 10 points. He also dished a game-high nine assists. Wesley Yates III added 13 points and had three steals, part of Idaho State’s 17 turnovers.