Any home remedies for removing grass stains from blue jeans? I didn't change into my"yard work clothes", and got grass stains on my favorite blue jeans. Ugh!!

I have just removed grass stains from my son's jeans!  After a regular wash I noticed they were still there and bright.  I poured hot water on the stain and some "oxy clean" , scrub and let it sit (I didn't let sit too long, I had to get the wash started).  Maybe repeat the process and scrub, let sit overnight.  I have just checked the pants and the stains are mostly removed with very little fain spot.  I am going to put the pants out in the sun and I'll be they'll be gone. 

Thanks, Carmina. I will try this. I washed them once treated with liquid detergent and it didn't all come off.