Novak Djokovic’s 16-match Key Biscayne winning streak ended, and his struggle to come back from an elbow injury continued. Djokovic lasted barely an hour at a tournament he has won six times, losing his opening match Friday in the Miami Open to Benoit Paire, 6-3, 6-4. The defeat was Djokovic’s third in a row. He returned from a six-month injury absence at the Australian Open and lost in the fourth round, and was upset two weeks ago at Indian Wells by Taro Daniel, a 109th-ranked qualifier. I’m trying, but it’s not working, Djokovic said. Obviously, I’m not feeling great when I’m playing this way. Of course I want to be able to play as well as I want. Just it’s impossible at the moment. That’s all. Against the 47th-ranked Paire, Djokovic dropped serve four times, returned poorly and had difficulty anticipating his crafty opponent’s drop shots.