Evidence continues to stream out of Belarus which makes it harder to predict Olympic shot put gold for Valerie Adams.

The latest results on the International Athletics Federation website show Adams' key rival Nadzeya Ostapchuk threw 21.58m in Minsk on July 18. The distance is 47cm more than Adams has thrown this season and 34cm further than her career best which she set at last year's world championships.

Ostapchuk now has the three best throws (21.58m, 21.39m and 21.13m) this year. She last threw more than 21m in 2005.

On May 31 in Rome, Adams seemed an unbackable favourite to defend her Olympic title. She threw 21.03m, obliterating Chinese rival Lijiao Gong by 1.24m and Ostapchuk by 1.45m.


Ostapchuk has awoken since. The pair now have the 11 best throws this season. No one else has thrown beyond 20.22m.

Adams is often cast as invincible but Ostapchuk's latest result adds a touch of vulnerability. If Adams does win, she stands to become only New Zealand's second track and field athlete, after Peter Snell in the 800m at Tokyo in 1964, to defend an Olympic gold medal.

Fortunately for Adams the 21.03m mark and her 21.11m effort on July 17 indicate her best is still to come. The 27-year-old is also an athlete for the big occasion, having been the best in the world outdoors since 2007.

Sadly, it seems regardless of Adams or Ostapchuk's efforts they will again fall short of the 22.41m Olympic record set at Moscow in 1980 by East German Ilona Slupianek who was returning from a ban for using steroids. The world record remains at 22.63m, set at Moscow in 1987 by Soviet Natalya Lisovskaya.