PORT ST. LUCIE, Fla. -- In 2009, the Mets spent a second-round pick on a left-hander from Melville High in East Setauket, N.Y. He needed Tommy John surgery before he threw his first professional pitch and didn't make his debut until three years after he signed.

Steven Matz eventually regained his health, helped pitch New York to the 2015 World Series and is firmly established in the big league rotation. And now the Mets are hoping history repeats itself.

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In 2013, they took another Melville High lefty, this time in the 29th round. New York couldn't sign Anthony Kay then but did three years later after he pitched collegiately at Connecticut. After taking him in the first round in 2016, the Mets learned he had an elbow injury that eventually required Tommy John surgery and would delay his pro debut until 2018.

Because they didn't overlap at Melville, Kay only knew Matz in passing. But he said the veteran offered him encouragement after he went under the knife.

"He told me just pretty much be patient, just listen to what they tell you and that's really about it," said Kay, who was in big league camp as a nonroster invitee this spring and had a locker near Matz's. "That's really all you can do."

Kay said he felt a little something in his elbow in his final amateur start, a no-decision in the NCAA tournament against Florida during which current Mets No.1 prospect Pete Alonso slammed a two-run homer against him. But he certainly didn't expect it would cost him hundreds of thousands of dollars -- New York reduced his bonus to $1.1 million after his post-Draft physical -- and two years of his pro career. He tried a platelet-rich plasma injection but ultimately needed reconstructive elbow surgery.

"When I found out it was torn, I was definitely surprised about it," Kay said. "It's tough because you want to be on the field as much as possible. Especially when you first get drafted, you want to make a good first impression.

"It was definitely tough not being on the field, not being able to show everyone what I can do. But now I'm good and healthy and I'm letting everyone know what I can do."

Kay finally returned to the mound last season and made 23 starts between two Class A stops. He recorded a 4.26 ERA with a 123/49 K/BB ratio in 122 2/3 innings, and he's now the most advanced starting pitching prospect in the system.

Like many pitchers who endure the arduous rehab process associated with Tommy John surgery, Kay has better stuff than he had before he got hurt. At Connecticut, he sat around 91-92 mph with his fastball and had a fringy curveball. His changeup was often his best pitch for the Huskies, but there were times last year when it was his third-best offering behind a 92-96 mph heater and a much improved curve.

Both Kay's fastball and curveball stand out for their high spin rates. He changed the way he throws his curve after returning to Connecticut during rehab and getting advice from former Husky and current Giants farmhand John Russell. Kay used to let his curve sort of float off his fingertips but now concentrates on ripping his arm down to his hip after he releases it.

"I think everything's a lot better," he said. "The fastball's a little bit harder, I've definitely got a better curveball. Just working on the changeup a little bit, getting it consistent. The way it's been this spring, it's been very consistent and it's got a lot of movement on it."

Matz first reached Citi Field at age 24, and it's possible that Kay could continue to follow his path and do so late this season. He'll begin this season in Double-A and could move quickly if he continues to regain the feel for pitching he had before he injured his elbow.