Everton director of football Marcel Brands has admitted that the club paid over the odds to sign Richarlison from Watford.
The 21-year-old became Marco Silva's first transfer as Toffees boss when he joined from Vicarage Road last month in a deal which could rise to £50m.
Everton were criticised by some fans and pundits for spending such a high amount of money on a player who had not scored since November, leading Silva to defend the outlay on the Brazilian.
However, Brands has now revealed that, due to the lingering animosity at Watford over what they considered "an unwarranted approach" for their former manager, Everton paid over the market value for Richarlison.
"We thought it would be a very difficult one because of the history of the clubs," the Dutchman told The Guardian.
"We were both convinced about him [but] I think with the situation with Watford, we had to pay a little bit more. I think maybe the market value was a little bit lower but, at the end, we are happy with him.
"We think he can be very special. He has a lot of speed, the capability to work; he is strong, he is tall. There are a lot of qualities for all the competitions in Europe. They are important qualities."
Richarlison starred in the Toffees' 2-2 draw with Wolverhampton Wanderers at the weekend, netting twice on his competitive debut before leaving the field injured.