By Felix Keith Arsenal supporters who doubted Kai Havertz should be made to apologise to the German forward, according to Rio Ferdinand. Havertz joined Arsenal in a £65million transfer from Chelsea in the summer window, arriving alongside Declan Rice, Jurrien Timber and David Raya. While fans were agreed on the importance of signing Rice from West Ham for a club-record £105m fee, the arrival of Havertz split opinion. He only contributed 32 goals and 12 assists in 139 matches for Chelsea, although one of those goals did win the Blues the Champions League final in 2021. Not everybody was convinc…