I know it is CRAZY but this is what I do for all the shirts, and stains on tee shirts. They are like brand new each time they are washed, after one wearing.
I spray with St. Moritz Well Done Oven Cleaner all the collars and cuffs and any spots on my tee shirts, and any other stains on my clothes, EXCEPT SILK!!! Put into machine at either 30, 40 degree C., easy care or cottons, with a capful of Vanish either for whites or Coloreds, with liquid ariel all temperatures. The clothes do come out beautifully clean.
I hide the bottle of the St Moritz in the garage, and put back immediately after use. I have been doing this for years and it really works.
I must point out though, that the American machines do wash much quicker, but the clothes are not as clean, as when washed in an English machine. My machine takes an hour and quarter for a color wash and about an hour and half for a white wash. That is the difference. By the way, the English machines are front loaders and only take 5 kilo = 11 lbs.