Franco was placed on the 10-day injured list Tuesday with a strained right quadriceps, Neil Solondz of the Rays Radio Network reports.
Franco left Monday's game against the Rangers with the injury, which turns out to be serious enough to cost him at least 10 days. Whether or not he's at risk of missing considerably more time than that is uncertain. Taylor Walls should become the primary shortstop in Franco's absence, opening up more at-bats at second and third base for Vidal Brujan and Isaac Paredes.