The Englishman has been heavily linked with a move away from Villa Park this summer, particularly to Manchester United.
A transfer would become significantly more likely should Villa go down this season.
"As a Villa fan I'd love him to stay. Jack likes to compete, he wants to do that at the highest level. He loves the club. He showed that in the Championship, he helped us get promotion, he battled hard in the Premier League.
"If that moment comes [when Grealish leaves], it would be sad to see because he is an exceptional person, not just player. But as a club, have we done enough to keep him?
"I don't think so and it's a big problem going forward as a club, because we may get good players through the youth system, but can we do enough to keep them?
"If he goes, I don't think he can be blamed."