Novak Djokovic responds to questions surrounding his water bottle

That clearly did not look like liquid, so what was it? Sources at Wimbledon told The Telegraph that there have not been any concerns about doping or illegal substances. Instead, it appears Djokovic was inhaling some sort of unmixed energy drink or pre-workout powder.

"You wouldn’t really get any benefit from doing it mid-match, but I’m sure this is isotonic,” one source explained. “A lot of players have started eating powder, even pre-workout isotonic powder. They’ve started eating it without water. It’s mainly pre-workout stuff because it gives them a buzz. I imagine it’s disgusting in the throat. It’s weird, but it’s what they are doing.”

When asked on Friday, Djokovic referred to the substance as his “magic potion.” He said he cannot reveal what it is now but will in time.

Djokovic has won 27 consecutive matches at the All England Club. He certainly is not going to change his routine now, and he even seems to be enjoying the mystique behind his “magic potion.”