After 14 years as the bass player for Metallica, Jason Newsted, citing “private and personal reasons, and the physical damage that I have done to myself,” quit the Grammy-winning heavy metal band on Wednesday, he revealed in a statement released by the group through its label, Elektra. Newsted, 37, who joined the band in 1986 after the death of bassist Cliff Burton, said that leaving the band was “the most difficult decision of my life.” The statement provided no details on exactly what physical damage Newsted had sustained. “We part ways with Jason with more love, more mutual respect and more understanding of each other than at any other point in the past,” said drummer Lars Ulrich.