Two days back, Poonia had missed out on a medal at the Perfontaine Classic Diamond League Meet at Eugene in the US when she managed a distance of 62.11m.
However, with a slight improvement, she won a silver in Portland event. The gold went to Russian Darya Pischalnickova, who threw the discus at an impressive distance of 66.38 metres in her fifth attempt.
Poonia's best throw came in her second attempt.