Two weeks before she died, on the Monday before Thanksgiving, cancer-stricken 6-year-old Damiyah Telemaque-Nelson told everyone not to wake her up unless it was to FaceTime with her friend John Wall.

When he learned of little Miyah’s demand, Wall couldn’t help but smile. She told the Washington Wizards point guard she was going to beat the Burkitt’s lymphoma that had been diagnosed more than a year earlier. She was upbeat and planned to attend the Wizards’ win over the Los Angeles Lakers last week. But Miyah’s condition quickly worsened, and she succumbed to the disease Monday morning, hours before Wall was to take the court opposite the Boston Celtics.

With his mind on far more important matters than a basketball game, Wall arrived at Verizon Center on Monday afternoon and executed the most extraordinary performance of his career in an exhausting 133-132 double-overtime triumph.

The emotional exhibition was the latest — and grandest — evidence of Wall’s maturation and ascension as a point guard.

After blowing a 23-point third-quarter lead, the Wizards overcame a seven-point deficit in the second overtime because of Wall. He scored 10 straight points in the period and was a menace in the open floor, converting two geometrically improbable layups in transition made possible by his blazing speed, including a three-point play to give the Wizards the lead with 44 seconds remaining.

“It’s great. It’s what he can do,” Coach Randy Wittman said. “I didn’t want to stop play. Anytime we could get a stop, we were going to push it. Even under a minute. I had a timeout in my pocket, but we didn’t want to stop John in those situations. He was really good at attacking the rim and finishing at the rim. That one finish was spectacular.”

Wall finished with 26 points, a career-high 17 assists, and seven rebounds. He became just the second NBA player in the last five years to record such a stat line. It was the fourth game this season — and the third straight — that the 6-foot-4 Wall fell just two or three rebounds short of a triple-double. He didn’t play the fourth quarter in one of those four games — a 30-point rout of the Denver Nuggets on Friday.

Through 20 games, the fifth-year floor general, often miffed over his standing among the league’s hierarchy, has unquestionably cemented himself as one of the sport’s elite point guards on both ends of the floor.

Offensively, Wall has entrenched himself among the league’s best passers. He was always content with creating for others, but with an improved supporting cast surrounding him he has taken the selflessness to the next level. He has exuded more patience and improved his ability to dial back his unmatched jets. He changes pace and ventures into the lane at will for kickout passes to open shooters. He is averaging a team-best 18 points per game but is forcing fewer shots.

Entering Tuesday’s slate of games, he led the NBA in assist percentage, which measures the percentage of teammates’ field goals that the player assisted, at 47.5 percent. He was tied for second in assists per game (10.4), tied for second in secondary assists per game (2.2), second in points created off assists per game (24.5) and third in assist opportunities created per game (19.8).

“I’m just reading defenses better,” Wall said. “Just everything. I think my whole game’s improved, just looking at how my game was my rookie year. Not going 100 miles per hour all the time. I can hit floaters, I can hit jump shots, and my decision-making is better. It’s all those little things. All those intangibles.”

Defensively, Wall is, as he and Wittman often put it, “the head of the snake.” His pressure is the turbine for the Wizards’ fourth-ranked defense based on points allowed per 100 possessions. He has always possessed the skills, but this season he has exerted the effort steadily and with fewer lapses.

Real plus-minus (RPM), a stat created by ESPN, estimates Wall has had the best defensive impact among point guards this season. His 2.83 defensive RPM is significantly better than second-ranked Elfrid Payton of the Orlando Magic’s 2.24, and his overall RPM of 2.92 is fifth among players at his position. Wall’s defensive impact is also evident in a more traditional way: He is second in the NBA with 2.2 steals per game and has had seven blocks in the Wizards’ last five games.

“I’m just trying to be more consistent on that end of the floor,” Wall said. “Last year I showed a lot of what I can do when I’m committed to it. Coming in, I was more of a gambler, reaching, going for extra things. Just sticking to the concepts and the basics, opportunities come to you. This team goes as far as I go — how I lead them on the defensive and offensive end.”

In an on-court interview show on the arena’s big screen following the Wizards’ marathon victory over the Celtics, Paul Pierce called Wall “a potential MVP.” Center Marcin Gortat took to Twitter on Friday night to declare to his nearly 68,000 followers that Wall is the best point guard in the NBA. He did not waver Monday night.

“John was truly amazing,” Gortat said. “I’m glad that he had a game like that. He kind of backed what I posted on Twitter a few days ago. He is definitely the top point guard in the league right now. He is playing tremendous basketball.”

But Wall’s mind wasn’t on basketball Monday. It was on his “little buddy” Miyah, whom he met in March and introduced to Nicki Minaj when he heard Miyah’s wish was to meet the hip-hop star and have one of her signature pink wigs. Within a couple weeks, Miyah met Minaj and had her own pink wig.

But Wall and Miyah stayed in touch. And on the day Miyah passed away, Wall paid homage the best way he knew how, with a win and a memorable performance as he continues his rise among basketball’s elite.

“This game was really meant for her,” Wall said.