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Samuel Groth, an Australian tennis player, unofficially surpassed Ivo Karlović's record for the fastest serve in tennis history. During a Davis Cup match against France in 2012, Groth unleashed a blistering serve that was recorded at 263 km/h (163.4 mph), eclipsing Karlović's previous mark of 251 km/h (156 mph) set in 2011.