Scunthorpe boss Alan Knill has made tentative enquiries about defenders Nathan Clarke and David Mirfin.
Clarke is a free agent after leaving Huddersfield while Mirfin spent the second half of last season on loan at Glanford Park from Watford, although any move for the latter appears to have been rebuffed.
"I spoke to Nathan's agent on Tuesday morning and that's about as far as it has gone," Knill told the club's official website.
"He is the type of player I like but at the moment we haven't really moved beyond the stage of talking.
"I spoke to Sean Dyche (Hornets manager) and he was adamant David was going to be at Watford - so if I am going to be honest I haven't really pursued it beyond that.
"He is a Watford player and it would be wrong for me to talk about somebody else's player."