Olympic pool turns a beautiful emerald.

Athletes not amused.

Jaw-dropping photos have emerged of the supposed state-of-the-art venue, the Maria Lenk Aquatics Venue, looking worse for wear. 

The diving pool has turned a brilliant shade of green, in stark contrast to the water polo pool beside it, which has pristine waters. 

The odd sight has prompted an outpouring on social media, with people likening the pool to something more suited to Shrek’s habitat than an Olympic venue. 

Others joked about athletes peeing in the pool, causing it to change color.