Late Rio call up for big serving Groth

Big serving Sam Groth has been added as a singles player to Australia's Rio Olympic tennis squad.

World No.168 Groth accepted the late invitation on Tuesday, boosting the Australian tennis contingent to 10.

Overall the Australian team at Rio now stands at 421.

Australian Olympic team boss Kitty Chiller said Groth was on the ATP tour playing in the United States when told to pack his bags for Rio.

"We've just finalised his entry and team leader Alicia Molik is in the process of contacting Sam who is in the States and very keen to get here," Chiller said.

"We will facilitate that flight as soon as we can."

Groth's mood quickly changed after he was bounced out this week in the Atlanta Open first round by a wildcard.

"Late call-up to join the @AUSOlympicTeam in Rio! Couldn't be more pumped," Groth tweeted.

Groth - who holds the world record for the fastest serve (263.4kph) - joins compatriots Thanasi Kokkinakis, John Millman and Jordan Thompson in the Rio men's singles draw.