John Wall, the foundation of the Washington Wizards’ rebuilding efforts for the past three years, has signed a multi-year contract extension, the team announced Wednesday afternoon.

According to a league source with knowledge of the situation, the deal is worth approximately $80 million over five years and will kick in at the start of the 2014-15 season. The agreement will keep the point guard within the Wizards organization through 2019, when Wall will be 28.

“Since drafting John with the first overall pick, we have been impressed with his maturation, hard work and commitment to our franchise,” Wizards owner Ted Leonsis said in a statement released by the team. “He is the cornerstone of our team, and we have clearly expressed our desire to build around him well before making it official by re-signing him today. We are extremely confident in his leadership abilities and are excited to see the continued improvement of the team.”

The Wizards will formally announce Wall’s new contract at a news conference on Thursday. Formal negotiations between the team and Wall’s agent, Dan Fegan, began two weeks ago and intensified while Wall was in Las Vegas last week as part of Team USA’s mini-camp for up-and-coming players.

Wall met with Fegan upon his return last Friday in Los Angeles, where he has been training this offseason. He has been in Washington this week and finally signed his new deal on Wednesday afternoon after working out at Verizon Center with teammates Bradley Beal and Otto Porter.

“I am both proud and humbled by the belief that the Wizards organization, the fans and my teammates have shown in me since I arrived here three years ago,” Wall said in the team-issued statement. “I can promise all of them that I will repay that belief by representing the city of Washington and doing everything I can to get this team back where it belongs.”

Wizards President Ernie Grunfeld had repeatedly stated his desire to keep Wall within the franchise for a long time and has built a team to complement the speedy point guard’s skill-set. Wall missed the first 33 games last season with a stress injury in his left knee and the team went 5-28, but he returned to lead the Wizards to a 24-25 finish and posted career highs of 18.5 points and 44.1 percent shooting while handing out 7.6 assists.

Since steals became an official statistic, Wall is the fastest player to reach 2,200 points, 1,000 assists, 600 rebounds, 200 steals and 90 blocked shots.

“John’s talent, ability and athleticism are unquestioned, but he is also a special player in terms of his will to win, unselfishness and ability to make his teammates better,” Grunfeld said in the statement. “The impact he has in all of those areas was evident last season and we look forward to both him and the team reaching new levels of success together.”

He also scored a career high 47 points with eight assists and seven rebounds in a win over Memphis and finished with 24 points and a career-high 16 assists in a road victory over the Los Angeles Lakers.

Wall is the first member of his 2010 draft class to receive a contract extension and the fourth point guard in the league with a maximum deal, joining former league most valuable player Derrick Rose and all-stars Deron Williams, Chris Paul and Russell Westbrook. In three seasons in Washington, Wall has averaged 16.9 points and eight assists, but has yet to make an all-star game or lead the Wizards to the playoffs.

Paul, Magic Johnson and Oscar Robertson are the only other players who have averaged or are averaging at least 16 points, eight assists, 4.4 rebounds and 1.5 steals over their careers.

“I’ve improved,” Wall said last week in Las Vegas. “I got better as a player. I think my jump shot is better, my IQ is better and just learning the game and being a better leader. I feel like I’m the player I want to be, but I still have a lot I want to do.”