Should either golf superstar capture the green jacket next weekend, McIlroy to complete a career Grand Slam and win his third major in a row or Woods for a fifth time to end a seven-year major win drought, he might just owe some thanks to 51-year-old Knox, who set the Augusta National members course record of 61 in 2003.
McIlroy was famously outplayed by non-competing marker Knox in last year's Masters third round, the Northern Ireland star shooting 71 to Knox's 70.
Woods, 39, has been nagged by back injuries for much of the past year, his quest simply to complete 72 holes becoming a soap opera sideshow.
"I'm playing in the Masters," Woods said. "I've worked a lot on my game and I'm looking forward to competing."
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McIlroy, 25, has won last year's British Open and PGA Championship and has established himself as the world's top player, but yearns for the only major crown to have eluded him.
Knox, already the envy of the golf world for his role as a marker if an odd number of players make the Masters cut, was deeply praised last year by McIlroy.
"Jeff is a great player," McIlroy said at the time. "He obviously knows this place so well and gets it round. I don't think I've ever seen anyone putt the greens as well as he does. He was really impressive. He played like he should have been playing in the Masters.