Instead of prolonging his greatness with more dazzling passes, Steve Nash has spent most of his time lately cooped up in a training room wondering if he’ll ever dish out more assists.

Nash described the past year in which he nursed persistent nerve issues in his back as “the toughest thing I’ve been through” in his 18-year NBA career. He also seems cognizant his return when the Lakers (16-31) visit the Minnesota Timberwolves (23-24) tonight at Target Center won’t spark the same excitement as when he earned two league MVP awards in Phoenix or when the Lakers acquired him in a blockbuster deal two years ago.

The Lakers have better chances these days competing for ping pong balls in the NBA draft lottery than a playoff berth. Lakers coach Mike D’Antoni conceded wondering if Nash ever would return. Nash also likely will sit against Cleveland on Wednesday in hopes of ensuring his body that turns 40 years old on Friday won’t break down again.

As Nash traveled to Vancouver, Canada for most of last offseason and on four separate trips this season to control the nerve damage surrounding his back and hamstrings, his personal trainer noticed Nash refusing to show any nerve irritation in his attitude.

“He’s approached this the same way as he’s approached everything in his career,” Rick Celebrini said in a phone interview with this newspaper. “He has the same commitment, professionalism and dedication that got him into the league in the first place. That’s why I’d run through a wall for him.”

Nash has appeared in only six games this season and averaged 6.7 points on 38.5 percent shooting and 4.8 assists. The Lakers could waive him this offseason via the stretch provision. Such a move would make Lakers pay the nearly $10 million owed to Nash through three seasons and ensure only $3 million counts against their salary cap annually. But Nash has vowed he’ll still tie up his laces.

“I can’t imagine anybody going through that type of work load,” Celebrini said, “if he was considering retirement.”

Nash described his trip to Vancouver during the Lakers’ recent 12-day, seven-game trip as “very tough.” Celebrini and Nash outlined in general terms the drills that ensure “postural stability.”

“You have to reinforce movement that puts the least amount of stress on the body,” Celebrini said. “If (Nash’s) leg is cast out and his foot lands in an awkward position, he will have to compensate somewhere else. But he doesn’t have the strength to do that. So it’s a matter of giving him the opportunity in terms of strength and control that positions himself to produce that movement. These are skills that involve cutting, changing directions, accelerating and landing from a jump.”

Nash has relished the monotonous work this past decade with Celebrini, a physiotherapist who works with Major League Soccer’s Vancouver Whitecaps and has served as a consultant with the NFL’s Seattle Seahawks, the NBA’s Dallas Mavericks and the NHL Players Association.

When Mavericks owner Mark Cuban chose not to resign Nash in 2004 out of fear his chronic back issues soon would end his career, Nash performed something far more impressive than conducting an offense. He teamed up with Celebrini, whose two-a day workouts for two months each offseason helped Nash last long enough to become the NBA’s current oldest player and climb up to fourth place on the league’s all-time leaders in assists.

“I’m extremely fortunate to have a chance to work with him,” Nash said of Celebrini. “He’s got an incredible talent for recognizing balances and improper movements. He’s able to clean up your movements so that you can be as efficient athletically as possible.”

Nash and Celebrini also endorsed the star guard lying on his back when he’s not in the game.

“We laughed at him a little bit,” joked D’Antoni, who coached Nash through five seasons in Phoenix (2003-08). “It was kind of odd. But he’s Canadian, so that’s OK.”

“He’s tried every important avenue. Rick has been a very important and integral part of what he does.”

Nash didn’t consider the practice humorous.

“To sit on the bench, relaxing and slouching is going to tighten up my back,” Nash said. “By lying down, my back can relax and still be in a position where I can go back in the game and not be tight.”

Nash’s methodical training, however, hasn’t eliminated the nerve damage stemming from fracturing his left leg last season, an injury that sidelined him for 24 games. He later missed eight more games, including two playoff appearances, because those nerves affected his back and hamstrings.

“What’s hard is when somebody doesn’t do everything he can,” D’Antoni said. “He’s doing everything he can. You hate it for him. But you appreciate what he does and for the franchise and the professionalism he has.”

The process hasn’t been fun, though.

“I came to L.A. with nothing but the highest of hopes and expectations. But it’s been nothing but personal disappointment,” Nash said. “At the same time, I enjoy taking on a challenge, growing and learning from it.”

The explanation for Nash having such a mindset seems far more simple than any of no-look moves or nifty crossover dribbles he once perfected.

Said Celebrini: “It takes a special person, doesn’t it?”

Staff writer Chris Trevino contributed to this report