It was confirmed on Thursday that Ziyech would be joining Chelsea at the end of the season for a fee rising to €44m.
And Boulahrouz says Ziyech will enjoy playing for manager Frank Lampard: “He is a trainer who wants to play football forward. With football that fits Ziyech.
“Even in the Premier League, Chelsea wants to solve everything by playing football. That is also nice for the ordinary football fan. I think the Chelsea before Lampard would have been less suitable for Hakim. Then the football there, as I call it, was not positive.
"Because of the temporary transfer ban, they were able to take the time at Chelsea to view players. That they end up at Ziyech also says something.
"Ziyech didn't just choose a club. He has been very satisfied with Ajax in recent years and in that period the necessary clubs have also come along."
"Now at Chelsea he ends up with a team where everything is perfectly arranged and in a city where it is great to live."