Metallica have shared three different versions of "Sad But True."
Their own version, "Sad But True (Take 36 - February 5th, 1991)," is taken from the Rough & Alternate Mixes section of The Black Album box set. They also posted versions done by St. Vincent and Jason Isbell and the 400 Unit from the massive covers collection The Metallica Blacklist.
Check out all three versions on YouTube.
The Black Album box set and The Metallica Blacklist are both out September 10th.