Fred Couples is to miss his first Masters since 1994 after pulling out of this year's tournament because of acute back pain.
The 56-year-old, who won the green jacket in 1992, remains a threat at Augusta National, sharing the 36-hole lead in 2012 and was one shot behind going into the weekend in 2013.
His career has been slowed by back problems in the last 20 years, with Couples admitting the recent pain has been too much for him to prepare or to compete.
Couples has played only three times this year, once on the PGA Tour. He missed the cut at Riviera while visibly struggling with his back.
Tiger Woods, Jim Furyk and Jose Maria Olazabal are all also ruled out due to injury and with Korea's Sang-moon Bae performing military service.
The field in Atlanta this year is 89 players, the fewest since 2002.