The fastest serve of a tennis ball was 251 km/h (156 mph) by Ivo Karlovic (Croatia) in the fourth set of a doubles match against Germany in the 2011 Davis Cup on 5 March 2011. The 2.08 m (6 ft 10 in) Karlovic”s previous best serve clocked in at 246 km/h (153 mph) in 2007.