The iconic trio of Cooper Cronk, Cameron Smith and Billy Slater have all retired from representative rugby, while Michael Morgan has suffered a season-ending pectoral tear.
As such, Meninga is keeping a close eye on the Origin series, which New South Wales Blues lead 1-0 after game one.
"A lot of weight will be placed on the Origin series this year and who wins it," Meninga said.
"Particularly around the spine, your nine, seven, six and one. Some of our greatest ever players have retired so our spots are wide open."