The defender cemented his place at Mansfield Town after a closely fought 1-1 draw with Forest Green Rovers at The New Lawn last night.
The 21-year-old was signed from Stoke City after a successful season on loan with the club.
He has become an integral member of Mansfield’s back three, after 31 solid appearances for David Flitcroft’s side.
Sweeney said: “The gaffer put it to me last month and I was really interested.
“Working with him and Futch day in day out I feel as though I’m improving, especially in the way he has us set up.
“We’re solid at the back and it’s something I was really, really excited about and I was buzzing when it was done today.”
The dominant centre half has contributed to Mansfield owning the best defensive record in League Two, with 23 goals conceded in 30 league games this season.
Sweeney said: “I have enjoyed my time at the club since the first day and can’t wait for the next couple of years.
“Thanks for the support so far this season it has been incredible. Let’s have a strong finish to the year.”
Mansfield Town sit at second place in the league, four points below Lincoln.
FREEVIEW: Speaking after a well earned 1-1 draw at Forest Green, defender @RyanSweeney97_ saluted #Stags’ boss David Flitcroft and assistant Ben Futcher for the player’s personal development.
For more, log in to https://t.co/MNH2M6FnKl pic.twitter.com/UaVUGw5BEW
— Mansfield Town FC (@mansfieldtownfc) January 30, 2019