Tennis fans are calling for sports commentator Doug Adler to be sacked for a comment made during Venus William’s second-round match at the Australian Open.

Viewers believe the 59-year-old former tennis pro, who is currently employed by U.S. television station ESPN, compared the world number 17’s on-court pressure to that of an ape.

“Horrifying that the Williams sisters remained subjected to it still in 2017." (Image: Getty)

One of those enraged by the statement isNew York Timestennis journalist Ben Rothenberg, who described the comment as "appalling stuff".

Many others agreed.

While Adler nor ESPN have spoken on the rogue comment, others were confused by the furore, explaining they interpreted Adler's description as

"

Reportedly, Adler later apologised while commentating the mens Escobedo-Ferrer match, saying he was sorry for the confusion caused, clarifying he was referring to the term "guerrilla warfare".