My local city golf course had crabgrass bad, one day we played and the crabgrass was all turning white and dying and rest of grass was ok. I asked one of the maintenance guys what they used. Generic Tenacity. I haven't tried it but it sure smoked those weeds.
https://www.domyown.com/tenacity-herbicide-p-1877.html
Not cheap. Ok for fescue, rye grass, bluegrass. Not recommended for bermuda or St Augustine.