Dr Lanny L Johnson, a pioneering orthopedic specialist who invented the tools used in Woods' knee operation in June, has warned the 32-year-old American not to rush back, or risk suffering long-term damage, The Telegraph reports.
"Other forces will try and hurry Tiger back, but he should take it easy. Dr Tom Rosenburg, who has performed his operations, is a great surgeon and if Tiger's smart, he will listen to what he has to say," the paper quoted Johnson, as saying.
"If you tear your cruciate ligament in American football, you can play within a year - and with full confidence within two years. Based on this, and the recovery period of other athletes, I am guessing that Tiger will need two years," he added.
Woods announced he was to have a fourth operation on his left knee two days after he defied doctors to win the US Open at Torrey Pines - his 14th major title of an incredible career.
Since that feat, achieved despite a stress fracture of the knee, he has been undergoing rehabilitation and was expected to be back in time for the 2009 Masters.
However, while he is likely to be fit enough to play next year, Dr Johnson's diagnosis suggests he could be struggling to be back to his dominant best in time for the summer of 2010.