Venus Williams was denied a chance to better her world record for fastest serve in women's tennis in absence of proper measuring technology at the Pan Pacific Open in Tokyo.
Williams blasted a 209km-per-hour serve during Thursday's 6-3, 6-7 (4), 6-3 win over Canadian teenager Eugenie Bouchard in the quarter-final match.
It meant that the 33-year-old American's serve of 207.6 km per hour, hit during the 2007 U.S. Open, stands as the fastest serve in women's tennis till date.
The multiple grand slam-winner, who has suffered a spate of injuries in the last two years, was herself surprised with the reading on the speed gun on Thursday.
"I saw that but I was like: 'Is that real?' So I don't know if that's real," Williams told the WTA in an interview. "I know I've been serving a lot harder this tournament than since I've come back from my back injury.
"I couldn't really serve that hard at the US Open and this summer. It feels good but I don't know if it was that hard. I hope it was... that's insane, it's awesome."
Williams, who beat world number two and top seed Victoria Azarenka in the second round, lost to Petra Kvitova of the Czech Republic 6-3, 3-6, 6-7 (2) in the semi-finals on Friday.
Photograph: Koji Watanabe/Getty Images
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