ESPN compiled a list of "the 20 most dominant athletes of 2018," and ATP and WTA No.1s Novak Djokovic and Simona Halep both made the cut.
Djokovic came in at No. 10 with a "Dominance Rating" of 1.205. (ESPN determined that number by comparing his statistics with those of other top tennis players from the past 20 years.)
In tennis terms, winning both Wimbledon and the US Open—plus taking two ATP Masters 1000 titles and making three other finals to finish the year as the world No. 1—very much qualifies as a dominant season.