Nataliya Dobrynska (Athletics)

Ukraine's Nataliya Dobrynska competes in the long jump event at the two-day international heptathlon meeting in Goetzis, in this May 31, 2009 file photograph.[Photo/Agencies]

All eyes will be on the mourning Ukrainian multi-eventer's every move as she takes on British darling Jessica Ennis in the heptathlon.

She emerged from nowhere to win the gold in 2008 and again upset the form book at the recent world indoor championships, beating Ennis and Russian world champion Tatyana Chernova to gold in a new pentathlon world record.

Dobrynska suffered heartbreak recently when her husband and coach Dmytro Polyakov died after a lengthy battle with cancer.