Both took the swings they flashed during spring training into their openers Thursday as Cardinals’ affiliates and minor-league baseball began their seasons around the country. Schrock, assigned to Class AAA Memphis, had a three-run shot that was one of two homers hit for the Redbirds as they began the defense of their Pacific Coast League title with a victory. Adolis Garcia, building off his strong spring, had the other homer. Knizner begins the year with Class AA Springfield, where the most playing time is available to him, and in a league that could test his offense all at ballparks built to make it thrive.