Port Vale assistant manager Mark Grew is worried that the excellent recent form of midfielder Anthony Griffith may alert clubs at a higher level.
The Montserrat international, 24, is an ever-present for Vale this season.
Grew told BBC Radio Stoke: "People say he's only got strength and tackling ability, but on the ball he's three times better than he was.
"He's worked hard at his game. I think there will be a lot of clubs interested in him just for that work ethic."
Grew added: "Both he and [fellow Vale midfielder] Sam Morsy are out every afternoon working on their passing.
"He knew when he came here that he was limited in some things and to get them right, you have to go out onto the training pitch and work hard at it."
Griffith joined Port Vale on a free transfer from Doncaster in 2008 and celebrated his 150th appearance for the League Two club with just his second goal in Vale colours against Northampton on Friday.
He netted the second, a stunning 35-yard effort, in a 3-0 win for Micky Adams' side at Vale Park.
Griffith made his debut for Montserrat earlier this year, captaining the small Caribbean nation in their two World Cup qualifiers against Belize at the end of last season.
However, on 7 October, he said he did not want his international commitments to affect his club form.