Yes against one playing his fourth game. There's a reason changeups are mostly used against opposite handed hitters. You use a changeup as a RHP to a RHH and it moves right into the hitters wheelhouse.. Just look at his splits this year. .525 OPS allowed vs RHB, .345 vs LHB.
Pratt probably is a light hitting righty, but I know Frelick is a light hitting lefty with bottom 5% exit velocities his entire MLB career. So again, explain to me why Frelick was the better option.