BOSTON — Mike Muscala will watch Tuesday night's season opener against the Celtics from the 76ers bench.

The 6-foot-11 reserve center, who is battling a sprained left ankle, was ruled out of the game Tuesday morning. Muscala said he's taking it "day by day." However, Sixers coach Brett Brown said he expects Muscala to be sidelined almost two weeks.

"I sprained my ankle about a month ago before the training camp," Muscala said. "So I was kind of dealing with a lot of swelling from that. It wasn't bothering me at all, but I kind of nicked it in the last preseason game" against the Dallas Mavericks on Oct. 8 in Shenzhen, China.

"So it's just trying to get it feeling good before the season gets under way."

Initially, Amir Johnson will get Muscala's minutes as the backup center to Joel Embiid. Brown also hopes to find ways to look at 6-10 rookie Jonah Bolden on the court.

The Sixers acquired Muscala this summer from the Atlanta Hawks in a three-team trade that also included the Oklahoma City Thunder.

He will make $5 million in this, the final year of his contract. Muscala averaged 7.6 points, 4.3 rebounds, and 1.0 assist in 20 minutes and shot 37.1 percent on three-pointers last season. He had seven starts in his 53 appearances.

The big man with shooting range averaged 4.0 points and 5.5 rebounds in 22.6 minutes in the Sixers' four preseason games, including one start.

Sixers reserve forward Wilson Chandler (hamstring) and reserve guards Jerryd Bayless (knee) and Zhaire Smith (foot) also will miss Tuesday's opener.