The fixture was probably the biggest of his career as London Broncos shocked Toronto Wolfpack in the Million Pound Game in Canada last year.
The 24-year-old from Essex had his fingers popped back into place before taking pain-killing injections at half-time to get through the game.
Walker was one of London’s stand-out players in Super League last season, and was confirmed as a Wakefield Trinity player on a two-year deal late last month.
“I was in quite a bit of pain but I didn’t want to go of,” said Walker looking back on London’s stunning win.
“I didn’t want the game to end in that way for myself.
“I was just trying to give everything I could.
“For about 10 minutes I was telling everyone not to pass me the ball because my fingers hurt too much. But once all the adrenaline kicked back in, I didn’t feel a thing.
“Apart from looking at it, I wouldn’t know that my fingers were broken.”
Walker made his Super League debut with London back in 2014.
The Broncos were relegated from the top flight in the same year, spending four years in the Championship before getting back into Super League.
Walker grew up on the border of Hertfordshire and Essex and revealed that he has Bradford Bulls’ Joe Keyes to thank for getting him into rugby league.
“Joe Keyes from Bradford Bulls went to my school and I sat next to him in Year 7,” said Walker.
“One year he dragged me along to his rugby club at Brentwood and I didn’t really look back from there.”
Walker has already had some experience of playing under Wakefield Trinity chief Chris Chester when the pair were together with Scotland Rugby League.
Walker has been named in the Bravehearts most recent World Cup qualifying squad and has earned four caps since his international debut in 2015.
The 24-year-old was keen to join Trinity when he heard there was interest from the Belle Vue club.
Wakefield avoided relegation on the final day of the season but had previously managed back-to-back top-five finishes and Walker is hoping to fire Trinity toward the play-offs in 2020.
“Looking at the past few years, they have been very successful, with the top-five finishes,” said Walker.
“So I thought it was the next step in my career, to play for a big club. And it excites me to get that opportunity.
“And I have known Chris Chester from the brief time when he was Scotland manager last year. I just wanted to play under him and try and progress my career.”
He added: “I think we want to be pushing for top five.
“Everyone wants to win trophies and stuff like that, so why can’t we do it at Wakefield?”
Walker got a taste of playing at Belle Vue as Trinity sent London down with a 19-10 win on September 15.
And the promising full-back is looking forward to playing in front of the Trinity support in the red, white and blue.
He said: “It was a great atmosphere and I hope that comes with every game.
“Playing in front of a big crowd and a good atmosphere, it really benefits us on the pitch, especially if they are cheering you on. And it is really exciting to be play in front of them, I am looking forward to it.”
Walker came through the academy at London before his professional debut five years ago.
He played over 100 times for London during his six-year spell and also spent time on loan at London Skolars and Hemel Stags.
Of his time in the capital, Walker added: “It was a great experience to go through everything. We were such a tight group.
“It was a bit of a rollercoaster, relegated, promoted and then relegated again.
“I don’t think I would change it, I really enjoyed my time there and I learnt a lot.
“And I am looking forward to carrying that on at Wakefield.”