Djokovic has sent out a warning to Nadal that he in his best form in over 12 months as the two prepare to go head-to-head for the first time on grass since the 2011 Wimbledon final.
The current Wimbledon betting odds at 888sport makes Djokovic the favorite going into this match despite that he will be playing against the world number 1.
The Serbian has rediscovered his mojo at SW19 and has looked more alike the former world No 1 who once held all four Grand Slam titles at one time in 2016.
Three-time champion Djokovic was the first man through to the semi-finals, reaching the last four of a major in more than two years by seeing off Japan's Kei Nishikori 6-3 3-6 6-2 6-2 on Centre Court.
Explaining the process which he underwent to get back closer to his best, 31-year-old Djokovic added: "I was putting a lot of hours on the practice courts and really being dedicated and motivated to get back on that level that I’m used to playing and have played over the years."
"Being absent from the tour for six months but then coming back, going back for surgery again as the season started, was too much mentally to handle."
It will be Djokovic's first Grand Slam semi-final since the 2016 US Open as he continues his bid to return to the top of the game.
Champion in 2008 and 2010, Rafael Nadal came through against Del Potro in a five-set epic that lasted four hours and 48 minutes on Centre Court to reach his sixth Wimbledon semi-final and 28th at the majors.
In a match that delivered quality throughout, Nadal recovered from two sets to one down to treat the Wimbledon crowd to a match few will forget.
The world number one, will be playing in his first All England Club semi-final since finishing runner-up to Djokovic in 2011.
Djokovic leads their epic head-to-head rivalry 26-25.