Hughton now hopes Holt, who fired 17 goals in the Premier League last season, can rediscover that same strike rate.
He said: "I'm pleased to have kept hold of Grant.
"He has been very good for this football club which is why the endeavours in the summer were to keep hold of him.
"It is similar to last season where he was slow starting. He then got into really good form and his goalscoring came in that period."