Article continues below
Former champion Fred Couples has withdrawn from the Masters due to "acute back problems", tournament officials have announced.
Couples, who has suffered from back problems throughout much of his career, won his only major title at Augusta National in 1992, carding a final round of 70 to finish 13 under par, two shots ahead of Ray Floyd.
The 56-year-old former world number one has recorded 11 top-10s in 31 appearances in the Masters, including finishing sixth in 2010 at the age of 50.
With Tiger Woods, Jim Furyk and Jose Maria Olazabal also ruled out due to injury and Korea's Sang-moon Bae performing military service, only 89 players remain in the field, the fewest since 2002.