Walker made his first start in left field Tuesday for Double-A Springfield, beginning his transition from third base, Rob Rains of StLSportsPage.com reports.
With Nolan Arenado set to stick in St. Louis for the foreseeable future, Walker was always going to have to move to a different position, most likely an outfield corner. He has been on a power binge lately, slashing .295/.347/.705 with five home runs in his last 10 games. Walker is on track to reach the majors sometime next season.