Johnson, 38, also is receiving interest for potential workouts from the LA Clippers, the Milwaukee Bucks, the Denver Nuggets and the New Orleans Pelicans. Pelicans coach Alvin Gentry and executive vice president David Griffin watched Johnson play in the BIG3 league in New Orleans last week.
Center Spencer Hawes is also working out for the 76ers on Thursday, league sources told ESPN's Adrian Wojnarowski. Hawes, 31, has played 10 years in the NBA and played with the Lakers' G-League team last season.
Philadelphia has 14 guaranteed contracts, with roster spot No. 15 belonging to guard Trey Burke at the moment. Burke has $405,000 guaranteed on his contract, and that will increase to $810,000 if he's not waived by Oct. 23.
Johnson was a seven-time NBA All-Star who averaged 16 points, 4.0 rebounds and 3.9 assists per game from 2001 to '18, playing for seven teams.
He most recently played in the NBA during the 2017-18 season with the Utah Jazz and Houston Rockets.
Johnson returning to the NBA through the BIG3 would be huge for the three-year-old league, because it has not previously had a player sign a major deal with the NBA. Former BIG3 player Xavier Silas signed a 10-day contract with the Boston Celtics in March 2018.
Johnson and the Triplets face the Killer 3s for the BIG3 championship on Sunday in Los Angeles.
Johnson was named MVP of the 2019 BIG3 season after leading the league in points (175), assists (31), 4-point shots made (four) and total field goals (63) and finishing second in 3-pointers made (16).
"Joe Johnson playing in the BIG3 has been a dream come true for basketball fans around the world," league founder Ice Cube told The Undefeated.
ESPN's Bobby Marks contributed to this report.
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