Having been dating a polo player for the last 6 years, I have gotten REALLY good at getting stains out of whites!
I always soak in cold water first. Then mix up a paste of oxyclean, tide, and a bit of water as needed to make it a thick paste. Take a spook and “paint” the stains with the paste. I let sit for at least 30min, sometimes I will even leave overnight. Pop them in the washer in cold water and boom. Brand new whites!
I do this about 4 times a week during some parts of the year. Obviously the excessive washing will ultimately damage fabrics but what can we do?!
Who decided white was a good color around horses anyway?!