John Wall, right, celebrates his game-winning three-pointer in Game 6 with fans at Verizon Center. (Jonathan Newton/The Washington Post)

When John Wall leaped onto the scorer’s table at Verizon Center and stood tall, flexing just seconds after hitting a season-saving three-pointer from 26 feet out in Friday’s Game 6 of the Eastern Conference semifinals, the symbolism wasn’t hard to grasp. It felt like Wall was taking the Washington Wizards, and the city’s fervor for the team, to new heights.

Atop the table, it was also clear Wall had also reached a pinnacle of sorts in his career. The shot that forced a Game 7 against the Boston Celtics on Monday night was both the result of a quick decision made with 3.9 seconds left in a game and the culmination of five years of working to develop a jump shot that wasn’t very good when Wall entered the NBA.

If there were any doubters left, the shot proved that as Washington heads to Boston for a chance to advance to its first Eastern Conference finals appearance since 1979, the Wizards have the best version of Wall yet at their disposal.

“You can tell, this guy’s been working,” center Ian Mahinmi, who joined the Wizards just last summer, said of Wall after practice Saturday. “From the time he first came in the league, where he was, like, mostly a driver and finisher at the rim, to now — he’s everything. Threes, twos, passes, leadership. That shows me more of his work ethic and his willingness to improve himself year after year after year. I just feel like I’m here at the right time.”

Indeed, Mahinmi’s timing is impeccable. Wall had neither the consistent stroke nor the confidence to shoot three-pointers, much less one with the season on the line, for the first few years he was in the NBA.

The point guard made fewer than 25 percent of his shots from beyond the arc during his first three seasons, from 2010 through 2013. In his rookie year, Wall made 34 of 115 three-point attempts over 69 games. He connected on 3 of 42 (7 percent) in his second year and 12 of 45 the next before making the leap in 2013-14, making 108 of 308, shooting 35.1 percent.

By the 2013-14 season, Wall had been working with well-known trainer Rob McClanaghan for more than a year. The young point guard had looked at Derrick Rose and Russell Westrbook, both longtime McClanaghan clients, and wanted be able to control his speed like they did, as well as add some range to his shot.

“I want to be great,” Wall said. “I don’t just want to be a good player and just use [my speed] to my advantage my whole career. At some point in time, the speed and athleticism are going to go away. So being able to knock shots, being able to post up smaller guards and learn how to attack at different angles and not use [my] speed at all times, that helped me expand my game.”

Wall started showing up for regular 7 a.m. workouts with McClanaghan during the offseason. To develop his jumper, the pair started with baby steps, both for the sake of Wall’s mechanics and his confidence. The point guard had never been labeled a shooter, so he didn’t have pride in that aspect of his game. He shot 29.6 percent from three his rookie season and started to second-guess himself from then on.

McClanaghan had him focus primarily on his midrange jumper for two years. Wall spent a whole summer drilling shots from 15 feet out — McClanaghan instructing him to hold his follow-through longer and use his legs more — before graduating to 18 feet the next summer.

When Wall finally started working on his three-pointer in earnest, McClanaghan only drilled him at the end of their workouts.

“It’s funny, when he hit that shot [Friday] night, I just thought of all the times he spent working on those threes when he was tired,” McClanaghan said in a phone interview Saturday. “Yeah, there were bad days where he didn’t hit any at all. There were some days where he hit a lot. But I think, having said all that, all that work he put in going back five years came through last night . . . he made that shot, I’m sure, when he was tired.”

None Wall releases the shot over Celtics guard Avery Bradley that splashes through the net with 3.5 seconds left in a 92-91 Game 6 win. (Jonathan Newton/The Washington Post)

In McClanaghan’s eyes, it was just as significant that Wall made the shot as it was that he took it in the first place. That play hadn’t even been drawn up for the point guard initially, and Wall started his night connecting on just 1 of 9 shots from the field. Both of those factors would have made Wall hesitant in the past.

But the development that resulted in a reliable three-pointer — Wall shot 89 threes this year in the regular season, making 32.7 percent — also created a more confident Wall. Friday wasn’t the first time he rallied from a slow start to drive his team to a win. In Game 4, the point guard matched his previous career worst by missing nine straight shots from the field to start the game. He saved the night by hitting his seven of his final 14 attempts to score 27 points.

“No. Probably not. I probably wouldn’t have,” Wall replied, when asked whether he would have been able to make those kinds of recoveries in games last season. “I probably would’ve been aggressive and got down on myself. But I understand this really, fully is my team. I’m the franchise guy, me and [Bradley Beal]. Coach tells me you have to be aggressive on both ends of the floor. We know you can score, but you also have to get your teammates involved, and I think me just being aggressive keeps the defense honest. I always said coming into this league, I’m not going to be one of those guys people can go in on screens my whole career.”

Now, Wall feels more prepared than ever to take the Wizards to the elusive Eastern Conference finals, where he has never been before. The evolution of his three-point shot was a part of his ascent into a star point guard.

The scorer’s table at Verizon Center was one summit. Another one, a steeper one, awaits in Boston, and Wall isn’t ready to stop climbing.

“My whole life I never had to use a jump shot. I was always better than everybody, faster, quicker, more athletic,” Wall said. “College was even the same. Then you get to the NBA, and shoot, the next guy’s just as quick, just as athletic, just as fast. So how can I separate myself from these guys? I think that’s the conversation — you ask Derrick Rose or Russell, they started to figure out, ‘how can I separate myself?’ And I figured it out. And it’s paying off now.”

More Wizards:

Celtics and Wizards have their own crosses to bear heading into Game 7

Late-game defense enabled Wall’s last-second heroics

The Wizards didn’t think too highly of Boston’s attempt at funeral attire

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