Following a truly historic night in Cardiff for Ireland, Martin O'Neill is now plotting for next month's play-off which will determine if the Boys in Green can reach their first World Cup in 16 years.
The news comes as a bitter blow to Martin O'Neill has he must now prepare for the crucial play-off next month without one of his key players.
Walters missed the Moldovan and Welsh games with a knee injury, and if Sky's report today is right, the injury is worse than first expected.
Walters, who has had two operations on his knee in the past 18 months, will therefore play no part in Ireland's playoff double-header next month.
The 34-year-old is still undergoing rehab work at Burnley, before being able to train again.
He was in the stands at the Cardiff City Stadium on Monday to cheer on Ireland during their 1-0 victory over Wales that secured O'Neill's men a play-off place. "I'd have to speak to Alan Byrne, our doctor, but he hasn't played for some time and the play-offs are in early November".
The Republic will learn at next week's draw whether they will face Switzerland, Italy, Croatia or Denmark.