Tokyo Olympics, day 12: Aussie Genevieve Gregson 'heartbroken' after horrific injury

Australia was holding its breath when the 3000m Steeplechase ended in disaster for our hope Genevieve Gregson on her birthday.

Australia have added another gold to the medal tally in the men's 470 class sailing but it's been a massive day of action on day 12.

The athletics was a mix of highs and lows for Australia with Australia getting Jess Hull and Linden Hall getting in the women's 1500m, and Peter Bol running a massive fourth in the 800m. But it was a day of devastation for Genevieve Gregson, who ruptured her Achilles tendon in the 3000m Steeplechase - on her 32nd birthday.

Away from the track, Australia has been able to celebrate a historic first medal in marathon swimming with Kareena Lee winning bronze in the women's 10km event.

But it was bad news for the Opals who were unceremoniously trounced out of the Olympics by Team USA in the women's basketball.

It's been a massive day of action on day 12 but it's a gargantuan day tomorrow with medal chances galore for the Aussies.