Sir Gareth Edwards would not be surprised if Mike Phillips starts at scrum-half in Wales' World Cup opener against Uruguay on Sunday.
Initially omitted from the squad, Phillips was recalled when Rhys Webb was ruled out by injury.
Gareth Davies and Lloyd Williams were Warren Gatland's original selections, but Edwards says Phillips may edge it.
"Mike has always been a great starter and I think Gatland may bring him on straight away," he told Sport Wales.
Wales legend Edwards added: "It will put Mike immediately in the firing line and be the game he requires, and that's not taking anything away from Gareth Davies or Lloyd Williams.
"But I like them to come on as impact players, they tend to have that little buzz and snipe about them.
"It will be physical and Mike Phillips is the sort of guy who likes an arm wrestle and it might very well be horses for courses."
Racing 92 player Phillips is the most experienced number nine in the squad, with 94 Wales appearances and five British and Irish Lions Tests to his name.
By contrast, Williams and Davies have 23 caps between them and Davies has not started a game for Wales.
Gatland believes Davies could be one of the tournament's surprise packages.
"Gareth is going to catch a few people by surprise with what he's got to offer in terms of his performances," the Wales head coach said.
Edwards, who played 53 consecutive matches for Wales between 1967 and 1978 as well as eight Test matches for the Lions, says Wales have a huge task to qualify from Pool A, which includes England, Australia and Fiji as well as Uruguay.
"My heart will be telling me that Wales will find a result from somewhere," said the 68-year-old, who is expected to be at Buckingham Palace for his knighthood investiture on Thursday.
"My head isn't totally convinced because it's so difficult to call. We can all be passionate and loyal, but I've been in the midst of many experienced players from all over the world in previous weeks and after debating it for hours, quite honestly we don't know.
"Matches could be decided by the width of a post, or width of a try line.
It's a tough shout and Wales area capable of first or second place - but it's a brave man who will put any money on it."
19:00 BST, BBC Two Wales, Thursday, 17 September. Available on iPlayer for seven days after transmission.