forehand winner to lead 4-3.
The Italian then hit a down the line forehand winner to lead 5-3.
Then ahead set point, Berretini struck a 138 miles per hour ace down the tee to take the set.
However in the following three sets, Djokovic's consistency and experience proved too much for the Italian.
The win for Djokovic would be his 21st grand slam match in a row and third consecutive Wimbledon title.
The 34 year old six time Wimbledon champion Djokovic this year has won the Australian Open, Roland Garros and Wimbledon and hopes to take the US Open singles title in New York City in September to complete the very rare calendar Grand Slam.
The Grand Slam; one of tennis largest prizes, was last won in 1988 by Steffi Graf of Germany.
The top ranked Barty took a 6-3, 3-1 lead before her opponent the 8th seeded Karolina Pliskova of the Czech Republic hit back with powerful serves and forehands to lead 4-3 in set two.
Then in the set two tie breaker, Barty netted four groundstrokes before double faulting while down set point.
However in the decisive set three, the Australian regrouped in time to strike several aggressive forehands as well as to mix in smart slice backhands to take the match after one hour and fifty-five minutes of play.
The 25 year old Barty took her first singles grand slam title at Roland Garros in 2019 after winning the junior Wimbledon singles title in 2011 as a 15 year old.