(I tried eating an underripe Keitt along with those two, but couldn't do it. I had to throw it away.)
If you have plenty of Keitt, throwing away a few is no problem. However if you have only a few, they will continue to ripen if not frozen first.
I use to believe that once in refrigerator ripening was not possible of mango per some previous reading. I have found this to be false as long as the fruit was not frozen in the refrigerator or freezer. I have pulled out refrigerated mango that were too green and hard and then placed them on a counter outside refrigerator and both cutup and whole mango have continued to ripen over the next day or two.
I first noticed this ability to ripen during refrigeration with my cut up Keitt mango placed in a bowl in the refrigerator a few years ago always seemed to taste sweeter in a day or two.
The refrigerator slow ripening sometimes does not get to the point of sweetness before evaporation, wrinkling, etc. of the mango to the point of it being undesirable. But, you can take it out and place on counter for a day & you might get to that point before the mango gets too dehydrated and wrinkled.
Of course if you have plenty ... discard any off flavored and grab another.
