Grant has been at the helm of the Phobians since November last year.
The former Westbromwich Albion forward is gradually building a win-some team after recording wins in most of their friendly encounters.
Kingston, who had two stints with the Accra-based giants during his playing days, has called on the club’s hierarchy to give coach Grant time as he works earnestly to bring the club back to its glory days.
“It’s very important for the management to maintain him. They should keep him for some time. He is doing well now. He is trying to bring his philosophy to the team,” he told Footballmadeinghana.com
“I believe the coach had some scout who scouted for him to get the players he needed. He has done a good job so far, it remains for them to be focused and get used to his philosophy. When they have the ball and when they don’t have the ball and others.”
Kingston also called on the fans to keep supporting the club.
“The team is very close to their heart. They should keep supporting the team. They should try and support the team as they were doing. I believe Hearts of Oak will come back to glory days very soon.”