 It was the highest-grossing sports film of all time, until "The Blind Side" (2009), which grossed $309 million (without accounting for inflation).It was also the highest-grossing fourth installment of a film in the United States and Canada, surpassing the record of "Sudden Impact" (1983).Stallone has been quoted as saying the enormous financial success and fan-following of "Rocky IV" once had him envisioning another Rocky movie, devoted to Drago and his post-boxing life, with Balboa's storyline running parallel to Drago's.