Any competent authenticator would know Mantle had a narrow window to sign Budig baseballs and any Mantle signed Budig ball should be examined very closely.
Secondly, a qualified Mantle examiner should have Greg Marino forgery exemplars in his files. If he did, he'd see this was signed by Greg Marino.
Zipper, that is what popped out at me, when I saw the listing before. it was on a Budig ball, definitely a red flag. As if the Drew Max cert was not enough of a flag.