Johannesburg: Novak Djokovic and Serena Williams are the International Tennis Federation`s world champions for 2013, according to reports.
According to Sport24, Djokovic captured the men`s award for the third successive year, and Williams took the honor for the fourth time.
Djokovic started the year by winning a third straight Australian Open and was runner-up at Wimbledon and the U.S. Open, the report said.
The 26-year-old Serb finished the season No 2 in the ATP rankings with seven tour titles, the report added.
The 32-year-old Williams won the French Open and US Open in 2013 to end the year No 1 in the WTA rankings for the first time since 2009, the report further said.
American twins Bob and Mike Bryan were named men`s doubles world champions for the 10th time in 11 years, while Sara Errani and Roberta Vinci of Italy took the women`s doubles award, the report mentioned.