There are two theories about Joao Felix, the 23-year-old Portuguese international who Chelsea are signing on loan until the end of the season.
One says he's every inch the €127million (£113m) player Jorge Mendes encouraged them to sign in 2019. The other is that he's a sulk - too immature to make it in any team that doesn't give him exactly the role he wants.
The only way to find out which theory is correct is to take Diego Simeone out of the equation, and this short term loan to Chelsea does exactly that.