Miller has impressed in pre-season and in the FFA Cup.

"I’m honoured to represent a club with such history, and I hope I can contribute during this season and help the club to continue forward and upwards," the 18-year-old said.

"Having been here for a couple of years, it is great to be rewarded like this, and it has been tough working to match the pace and intensity of training with the first grade squad.

"But staying in this environment, and being around the leaders and elite defenders we have has helped me to improve my game and work towards this opportunity.”

Miller was a junior with Manly United and spent a season in Sydney FC's youth team.

He played 93 minutes in the FFA Cup Round of 16 clash that the Mariners won on penalties.

"Lewis is a great kid, and this is just reward for the hard work he has put in both on the training ground and the pitch,” Central Coast coach Alen Stajcic said.

"It’s important that we reward our talented young players, so this is a good stepping stone for him and Mariners fans can know that he is certainly a player to keep an eye out for moving forward."