A 23rd female massage therapist is now suing Deshaun Watson ... claiming she's decided to file the docs after watching the HBO special on the quarterback earlier this month.
In the lawsuit, filed in Harris County, Texas on Tuesday and obtained by TMZ Sports, Nia Smith says Watson was sexually inappropriate with her during three separate massage sessions in 2020.
Her allegations -- which are similar to the other 22 masseuses who have sued Watson in the past two years -- had been made public before .