Drogba did not start but came on in the second half and helped provide the inspiration for a 2-1 come-from-behind win in Recife.
"I was disappointed [not to start]," the 36-year-old Drogba said. "But I have to show my respect to those that started.
"When I went in, I just wanted to help the team to win the match and I did not need this disappointment in order to be motivated.
"I don't know how long I played but I knew it was important to give something extra.
"Japan weren't very dangerous but we trailed and had to come from behind to win. It is a beautiful victory and we are happy with the result. We've prepared for many weeks for this game and it was important to start the competition on the right foot.
"This result will be very important especially if we play a good game against Colombia."