The Millers have splashed £500k for Ladapo's services plus another £150k in possible addons, showing a big intent to gain promotion back to the Championship at the first asking again.
Signing a 3 year deal today, The Millers have beat off a number of other clubs in both the Championship and League 1 to secure his services.
Boss Paul Warne said: "Freddie is someone we have tried to sign in the past. There have been numerous phone calls lately. We have been chasing him, along with many other clubs, for many weeks."
Meanwhile, Ladapo went onto Instagram.