Australian Sam Groth shattered the mark for the fastest recorded serve in professional tennis three days ago at an ATP Challenger event in Busan, South Korea. The strapping 6-foot-4, 210-pound journeyman blasted an ace past Uladzimir Ignatik of Belarus registering an astounding 163 mph (263 kph) on the radar gun, far surpassing the record of 156 mph set by Croatia’s Ivo Karlovic during a Davis Cup match against Germany in March last year. Groth also had serves of 159 mph and 158 mph during the second-round match. Ignatik prevailed, though, 6-4, 6-3. The 24-year-old Aussie, ranked No. 340, turned pro in 2006 and has played primarily on the Challenger circuit. He has a 2-3 career record in Tour level matches and did take a set off Gilles Simon at Nottingham in 2008 and Mardy Fish at the U.S. Open in 2009. Groth reached a career-high No. 220 in the world on November 16, 2009. After the match, Groth tweeted, “Lost 4 & 3 average! Did hit a 263 kph serve though in for an ace.” The ATP doesn’t officially recognize service speed records because of the variance in radar guns, but confirmed that the event used approved equipment, and that other data gathered appeared within normal range.