Johnson described Hughes' winning goal against Forest Green as world class.
Stephen Hunt put County ahead on his return to action after injury but Isiah Rankin levelled for the non-league side.
Schmeichel preserved the host's lead with late saves to ensure they host Wigan on Saturday.
"Hughesy stuck a 'worldy' in. That's 19 goals now for the season so he's not doing too bad. He's a different class and so was Kasper (Schmeichel) at the other end with his saves," said Johnson.
"He made two great saves in the closing minutes. If he hadn't we would have been going to Forest Green on Saturday for a replay. Fortunately for us we've got Wigan at home now and we can all look forward to that."