A first-call session guitarist in Nashville, Justin Ostrander’s got superhuman chops, and he brings just the right thing to the table every time, no matter the setting. Big, crashing power chords and rock ’n’ roll string-throttling for Chris Janson’s “Buy Me a Boat”? Check. Supple but cinematic textures for Kameron Marlowe’s “Giving You Up”? Can do. Lyrical licks and chunky rhythms on Riley Green’s “Runnin’ with an Angel”? Comin’ right up.