Ben Simmons has officially agreed to a new long-term deal with the Philadelphia 76ers, the team announced on Tuesday.
The Sixers confirmed a five-year extension, starting in 2020, but did not reveal the terms of the contract - reported to be a max deal worth $170million.
Simmons, who turns 23 on Saturday, was in the last year of his rookie contract.
"Ben Simmons is an important piece of our core and he is one of the NBA's most dynamic and talented young players," general manager Elton Brand said.
"It was a priority for our organisation that we finalise a contract extension with Ben this summer. He was Rookie of the Year in his first season, an All-Star in his second and we expect him to continue grow and succeed for seasons to come.
"Ben positively impacts the game in so many ways and we look forward to continuing our championship pursuits with him as one of our leaders."
The Australian was drafted by Philadelphia with the number one overall pick in 2016 but missed his entire rookie season due to a foot injury.
Simmons finished last season averaging 16.9 points, 8.8 rebounds and 7.7 assists per game and helped lead the Sixers to the second round of the playoffs, where they were agonisingly beaten by eventual champions the Toronto Raptors.