John Wall is greeted by the bench after securing the victory over the 76ers. (Toni L. Sandys/The Washington Post)

The Washington Wizards had to watch a major piece of their foundation go down in order to get a reminder that the initial building block of the franchise’s rebuilding efforts can still deliver when it counts.

John Wall has taken his lumps in recent weeks, deflected criticism and battled through a slump that had him pouting and doubting. Wall even invited his mother, Frances Pulley, up from Raleigh, N.C. last week to provide some home-cooked meals — including his favorite shrimp — and encouraging words.

All were needed on Sunday night, as the Wizards let an eight-point lead evaporate into a three-point deficit and then lost Bradley Beal to an ankle injury before Wall scored the game’s final six points — two huge jumpers and two huge free throws — and recorded a game-saving blocked shot to secure a 90-87 victory at Verizon Center.

“I like the ball at the end of the games,” Wall said after scoring a team-high 16 points with six assists and five rebounds. “With those type of plays, you want to be the hero. You want to have the pressure. Sometimes you’re going to succeed. Sometimes you’re going to fail, but as long as you have confidence and believe in yourself, you’ll be all right.”

Beal had 14 points before going down and had to watch the rest of the game in the training room. He said the X-rays didn’t reveal any serious damage, but was moving throughout the locker room on crutches after the game. He will be evaluated further on Monday.

“Whenever you have something like that, like an ankle sprain, it feels bad. I’m thankful it wasn’t my knee or anything too serious,” Beal said. “I’m grateful I have my teammates to have my back. John definitely made some big shots down the stretch. I’m glad they stuck with it.”

In the first six weeks after returning from a stress injury in his left knee, Wall had shown flashes of his ability and brought a jolt to a team that had been wallowing below mediocrity for some time. The Wizards (19-39) are now 14-11 since Wall suited up, but rarely had he been asked to carry his team offensively or impose his will on the final outcome. Opportunities are created, not forced, and after enduring a rough patch of poor shooting and passing, Wall was ready to seize the moment. He helped his team snap its first two-game home losing streak since he returned — and avenge an earlier loss to Philadelphia.

“I think it was big for him, especially since he has been struggling,” reserve forward Trevor Ariza said. “I think that just shows he’s growing up throughout the year and the steps that he’s taking to become a better player.”

Wall had been relatively quiet for most of the night, aside from a dazzling first-half drive in which he stumbled, recovered and made a 360-degree spin move around Spencer Hawes before making a layup. But he had no choice but to step up after Beal fell to the ground and grimaced with 2 minutes 8 seconds left in the game.

Beal trailed 76ers all-star point guard Jrue Holiday (14 points) along the baseline and jumped, thinking that Holiday was going to shoot. Instead, Holiday dropped the ball off to Thaddeus Young, who made a floater over Wall and Nene to give Philadelphia an 87-84 lead as Beal landed awkwardly on his left ankle. Beal collapsed to the floor and reached for his ankle. Unable to move, Beal was so overwhelmed that he couldn’t feel his injured left foot.

“I guess that’s what happens when you go into shock,” Beal said afterward.

But the real shock had taken over the building, especially after teammates Jan Vesely and Chris Singleton picked up the 19-year-old rookie and carried him to the locker room for evaluation.

“We were all collectively kind of holding our breath, not knowing what was going on,” reserve A.J. Price said, “but on the other hand, we had a game we had to win, so we couldn’t dwell on that too long.”

Wall initially erred after Beal was injured, losing the ball to Young — his second turnover of the game — but he quickly made amends. He hit a pull-up jumper to bring the Wizards’ deficit to one point, then rebounded a Holiday miss, and darted up the court before drawing a foul. Wall made both free throws to give the Wizards an 88-87 lead and then the 2010 No. 1 overall pick chased down 76ers swingman Evan Turner, who went second in the same draft, to block his driving layup.

After Martell Webster (16 points) missed a jumper, Nene, back in the lineup after missing the previous two games with a sore right shoulder, secured the offensive rebound. With the shot clock winding down, the ball made its way to Wall and the 76ers stepped away to let him shoot from 20 feet. Wall has had difficulty making and taking jumpers throughout his career, but he rose up over Dorell Wright without any hesitation and stroked the net.

With the crowd cheering, Wall raced back to his bench with his eyebrows slanted toward anger and nostrils flaring determination. Wall thumped his chest, then stared down the crowd.

“My coaches told me I had to be more aggressive in the fourth quarter. Luckily it went down,” Wall said. “I’m more comfortable taking them, I just have to be more confident taking and knock them down if the defense is going to play off me and give it to me. I just have to take it with confidence.”

All five Wizards starters scored in double figures and recorded at least one blocked shot, with Emeka Okafor recording his 16th double-double with 12 points and 16 rebounds and Nene scoring 15 despite having his shoulder heavily bandaged. Nene made a layup to give the Wizards an 82-74 lead, but Philadelphia went on an 11-0 run before Nene ended a more than five-minute scoring drought with another hook shot.

“That was a gutty win for our guys,” Coach Randy Wittman said, adding that Wall, “wants to win as bad as anybody.”