That is what I believe. Things like Hamstrings, turf toe, and Groin polls were all solved with the needle back in the 70s and 80s. Nowadays players are thinking about their careers and will not just take a shot on game day to cover up the pain of these type of injuries. It was just understood that a player injured in the 1st half, would be back in the 2nd half after spending some time with the Team Doc and the needle. There is a scene in the movie North Dallas Forty where a veteran is used to convince a young healthy rookie on how to take the needle for game day.