The 21-year-old stole the headlines following his last second try in the Club’s dramatic 2020 Betfred Super League Grand Final victory over Wigan. He went from strength to strength in 2021 following a string of impressive performances – most notably two hat-tricks in Saints’ Super League victories over Hull FC.

Welsby, who signed for Saints Academy in 2014 after playing amateur rugby for Shevington and Blackbrook, was named Betfred Super League Young Player of the Year for 2021 and took home Player and Players’ Player of the Year trophies at the Club’s end of season awards.

His meteoric rise was rewarded after he was given the number 1 shirt ahead of the 2022 season and he hasn’t disappointed, scoring 6 times in 15 appearances thus far

In total Welsby has pulled on the Red Vee 70 times scoring an impressive 32 tries.

On signing his extension, Jack said: “It’s another dream come true. I have always wanted to be at this Club, ever since I first joined, I only ever saw myself playing for Saints.

“I have only ever known this group of players I am playing with at the minute and the likes of James Roby and Jonny Lomax have had such a big impact on me and on this Club as a whole.

“When I was given the number one shirt last year, it was a big deal for myself. I might not have said it, but I have always seen myself playing at full back. I have been very fortunate to have the likes of Paul Wellens and Jonny Lomax around me and I have learnt a lot so far.

“I am by no means the complete player yet, I have a long way to go and I am looking forward to the years ahead.”

Head Coach Kristian Woolf said: “Jack’s signature is an outstanding signing for the Club. Over the last couple of years, he has progressed from being a talented young player, into a bloke who is one of the first picked in our team every week.

“He is a leader in the group and will only continue to improve in his on-field performances and his influence as a leader. He has already had a massive impact on the competition and on our team in particular. This new deal is a great opportunity for him to continue his development and continue to develop that path of becoming one of the best players in Super League.”

Welsby was called up to the senior England squad for the first time last season and was included in the England Training squad recently, alongside Matty Lees who signed a contract extension earlier this week.