Transfer window: When it was introduced, dates & everything you need to know Unknown 04:12 Goal brings you all you need to know about what has become a key fixture in the calendar of football across the world Share this Share on FacebookTweet on TwitterPlus on Google+ Related PostsVirat Kohli's Indian cricket team can make history in South Africa: Lalchand Ra...Durant, Warriors top Mavericks 112-97Roger Federer wants to play tennis for 'a few more years'Australia hit all-time high as USA end 2017 on topJose Mourinho runs afoul of Football Association for pre-Manchester derby comme...Tottenham Hotspur's away form in Premier League adds to task vs Manchester City