LONDON: Little known Australian player Sam Groth has fired down the fastest recorded serve in professional tennis, a 263kph rocket in a Challenger event in South Korea.

The ATP Tour said on Saturday that Groth, ranked 340 in the world, produced the serve in a second-round match against Belarusian Uladzimir Ignatik in Busan.

Groth's effort beat the previous fastest-recorded serve of 251kph sent down by Croatian Ivo Karlovic in a Davis Cup tie against Germany in Zagreb in March, 2011.

While the ATP does not officially recognise serving speed records because of the variance in radar guns it confirmed “the event was using approved equipment, and that other data gathered appeared within a normal range.”

Melbourne-based Groth, 24, lost the match 6-4 6-3.