And the Dutchman admits Cristiano Ronaldo will be a big influence on his decision.
"During the season, at the club, and during the various competitions, you really do not have time to reflect. But there are times when I realise that this is not normal. Like recently, when I dined with my football friends of the past," he recalled.
"Adidas organised that dinner. There were also childhood friends and we started remembering. We came to the conclusion that I always wanted to be Cristiano Ronaldo when we played football in the garden . That was especially in his time when he played for Manchester United.
"My first football shirt was also his. That dinner was right after the games with Juventus, in which I had to fight with Ronaldo himself, something that is really special."