The fast bowler, who has signed his first professional contract with the Club, made his England Under-19s debut in 2018, taking figures of 2-20 in the Youth Test against South Africa in July.
The 19-year-old made eight appearances for the Second XI last season, taking 11 wickets with best figures of 4-90.
Head of Cricket, Dave Houghton said: “Sam has worked hard on his game and Steve [Kirby] has been impressed when he’s seen him in action.
“He’s a young guy with bags of potential and someone we feel has a bright future in the game.
“He will now get the opportunity to work full time with Steve and the rest of the first team squad, and we look forward to watching his progression.”
© Cricket World 2018