Saints have won the race to sign second rower Joe Batchelor from York City Knights on a three-year contract.
The 23-year-old back rower will link up with his new teammates for the 2019 season.
Batchelor, the brother of Wakefield Trinity star James, first played under York head coach James Ford in the Wakefield College team, before joining Sheffield Eagles’ academy and then having a year in Australia.
He returned to the UK in 2016 for a spell at Coventry Bears and moved to the Minster city the following year.
An outstanding 2017 saw Joe named both the Player of the Year and The York Press Player of the Year following his debut season at the club, which saw him score 15 tries in 22 appearances.
Despite attracting interest from Super League, Batchelor signed an improved deal at York and to date has made eight appearances in 2018, scoring eight tries – including a try against Catalans Dragons in the Ladbrokes Challenge Cup.
“Joe is a player we have had our eyes on this season,” Saints Head Coach Justin Holbrook said. “He has been a real standout in Betfred League 1 this year and has been very consistent for a competitive York side.
“He is a strong running second rower with good skill and he also has a great work ethic. He has now matured as a player and hopefully he will continue to improve with us at Saints.
“We are looking forward to welcoming him into our system.”
Commenting on his move to the Saints, Joe said: “I’m delighted to have signed with St Helens from next season and have the unbelievable opportunity train in a full time environment with world class players and hopefully play Super League rugby.
“I would like to say a massive thank you to everyone at York, especially Jon, Fordy and all the coaching staff for the amount of hard work they’ve put into getting me to this stage.
“I am still 100% committed to finishing my year at York and making sure it ends with promotion to the Championship.”