Perhaps one of the segments on his life's preface should be "Last Chance" -- the first word is on the dorsal side of his right hand and the other on his left, etched in 2009.
"Against All Odds" should be another, only tattooed across the chest a month ago.
"I'll be back on the court again, who would have thought that," says Walker with a beaming smile that camouflages the life of a young man once caught up in a surreal world of alcohol and drugs.
The new generation of Hawks fans can be excused for asking "who's that?" when they see him on the bench against the Otago Nuggets today when the Bartercard National Basketball (NBL) match tips off at the Pettigrew-Green Arena in Napier at 7pm.
In fact, this former Te Mata School pupil oozed talent, so much so that when he attended the now defunct Church College in Hamilton because of his Mormon faith he caught the eye of myriad talent scouts.
At the high school he was voted the MVP when Church College won the New Zealand secondary schools' crown in 2002-03.
By the time he was 17 in 2003 and still at school, he made his debut with the Waikato Titans who lost the final that year.
The following year, Walker, who made the New Zealand Under-18 team, found himself in the New Zealand Breakers development squad.
"I was a little burned out after that so I took a little time out from the NBL and just played in age-group teams in the second half of the year," he says, before contracts with the Nuggets (2005) and the title-winning Hawks in 2006 beckoned under coach Shawn Dennis.
So what happened since 2006 when the prodigal son of Hawks, who didn't go beyond the playoffs, found himself in basketball wilderness?
"I was being in the world," he says cryptically before elaborating. "The time went fast. One day I was 22 and the next time I woke up I was 25."
In a nutshell, Walker reveals, without any facade of regret, he had lost his way at high school, mixing with the wrong crowd.
"I should have listened to my parents," says the son of Robert and Angela Walker who now works as support worker for Child, Youth and Family to counsel youngsters straying off course in life.
The Last Chance and Against All Odds, no doubt, come like a timely shot from inside the arc to beat the shot clock in the dying seconds of a playoff-clinching game.
"I haven't lost the dream or the goal. I always knew I was going to come back to play," says Walker who has been clean for two years.
His older brother, Scott Walker, 29, living in the Gold Coast, never gave up on him until he returned to live with his parents.
Sam Walker knows talk is cheap so he hopes to find his mojo on the court again tonight, not only to try to mould a career in basketball but also repay the faith Hawks coach Tab Baldwin and captain Paora Winitana have placed in him.
Having overcome his Achilles injury, Baldwin says, Walker will be the third big man in tonight's game.
Fuelled with passion, Walker brings strength and shoots well as a small forward who relishes playing inside and outside.
"He's a skilled player but he's had some off-court issues," says Baldwin, adding Walker needs to settle down to find a modicum of traction in the game of life and, consequently, he'll find his prowess on the court of contention will take care of itself.
"I'm very pleased with his progress. It's Sam's first step into professionalism and also a professional career.
"He can chalk up the past few years to life's experiences."
Fundamental to Walker's success will be a respect for his body, which will not only benefit him but also earn respect from the team and the sport.
He lauds inspirational captain Winitana, a Mormon bishop, for his "tremendous influence" on Walker who "allowed Paora back into his life".
Baldwin says if humility and honesty didn't form the foundation of his comeback the Hawks wouldn't be investing in Walker.
The five-time NBL title-winning coach lauds last weekend's home crowd who were the ideal catalysts for a resounding victory over the Southland Sharks.
"But when the game got a bit lopsided the fans seemed to have lost that enthusiasm," he says, urging the PG Arena faithful to keep it going to the end.
"We want our fans not to just be spectators but also participate in the game."
For Winitana it'll be his first home game tonight after sitting out last Sunday because of his beliefs.
