Simmons was injured Friday during the final training camp scrimmage at Stockton University in New Jersey. The Sixers said Simmons rolled an ankle, and X-rays and an MRI revealed a fractured fifth metatarsal bone.
The Australian forward played at LSU last season. He missed time early during his stay with the Tigers while waiting for an ankle injury to heal, and also left an NBA Summer League contest in July after suffering cramps in both legs.
Simmons' injury is the latest blow to a franchise that has been beset in recent years by injuries to their players. Joel Embiid, the No. 3 overall pick in 2014, has yet to play because of surgeries on his right foot. Nerlens Noel missed his rookie year in 2013 with a torn ACL. Jahlil Okafor had his rookie season cut short with season-ending knee surgery on his right knee. He sat out practices this week because he still experienced soreness in the knee.
It's become a bit of a theme in Philly the last few seasons, ending with last season's 10-72 mark that earned them the No. 1 pick.
Simmons became an instant fan favorite before he ever played a game and expectations were high that he was the cornerstone player that could eventually help turn the Sixers into playoff contenders.
"It means a lot, just to see people wearing my jersey around Philly, it's kind of weird," he said this week. "I'm just looking forward to hopefully giving back to Philly."
He'll have to wait.
Simmons was scheduled to start for the Sixers in their preseason opener Tuesday against Boston. Simmons, the 6-foot-10, 250-pound forward out of LSU, was Philadelphia's first No. 1 pick since they drafted Allen Iverson in 1996. He led the Sixers to their last NBA finals appearance in 2001.
Coach Brett Brown planned to use Simmons all over the court, even at point guard. He impressed his teammates with just one week of NBA training camp.
"I never played with somebody," like him, forward Dario Saric said at training camp. "Everybody puts pressure on him but I think he'll handle this."
Simmons averaged 19.2 points, 11.8 rebounds and 4.8 assists, the only SEC player ever to finish in the top five in all three categories. But the Tigers were only 19-14, failing to make the NCAA Tournament.
Simmons, who grew up in Australia before moving to Florida for three years of high school at Montverde Academy, signed a $20 million sneaker deal with Nike before the draft.
He never demonstrated he could make jump shots consistently, rarely shooting from outside and going only 1 of 3 from 3-point range all season. He also exhibited an inclination to pass, rather than create his own shot, in the late stages of close games.
Simmons also had academic issues that made him ineligible for the Wooden Award, which is presented to the nation's top college player.