Philadelphia 76ers star Ben Simmons will undergo further lower-back testing Monday and has been ruled out against the Atlanta Hawks that night, reports Adrian Wojnarowski of ESPN.
Simmons underwent an initial MRI on Sunday after re-aggravating the injury minutes into Saturday's defeat to the Milwaukee Bucks. He left that game with 7:16 remaining in the first quarter and didn't come back.
The All-Star made his return to the lineup Saturday after missing Thursday's contest with back soreness.
Simmons is averaging 16.7 points and 8.2 assists for the 76ers this season.