How do I get this weird stain out of my polo?

[Max727]

I have this Kent Wang polo that I really like, but I got this weird stain after washing it the last time and I have no idea how to remove it. I had been soaking part of the shirt in vinegar to remove some antiperspirant stains, so maybe it's related to that? The armpit stains are gone, but this showed up. I tried soaking it in vinegar, but it didn't help. I wash the polo on delicate cycle in cold water and then hang it to dry.

Side question: Long term, should these polos be hung or folded?

 

[endag]

Dish soap? I fold 'em, treat them like I do my sweaters

 

[double00]

censor ruined the joak smh

 

[GaiusM]

If it's all cotton try shampoo with a bit of rock salt. Wet the area first, put a little shampoo on it, massage in, then sprinkle salt and rub with fingers.
If all else fails lemon juice works on white cotton, no clue about colors.
Test all methods on hidden area like under the collar first.

 

[Oswald Cornelius]

Try mixing blue Dawn dish soap 1 to 1 with baking soda. Spread on front and back of stain and let dry overnight. Wash on warm. Air dry.

Might not work, but it's often a good fix for set-in stains like this one.