The free agent signee, averaging 5.7 points and 5.7 rebounds in 23.3 minutes per game on the season, suffered the injury last week in the Lakers' 100-91 loss to the Sacramento Kings when colliding with center DeMarcus Cousins. He re-aggravated the injury later that game when teammate Pau Gasol inadvertently landed on his foot.
McRoberts played in the Lakers' next four games following the Sacramento loss but sat out Monday's practice.
"It just hasn't really got any better so I'm just going to take some time and see if a little time off of it, I can get healed up," McRoberts said.
The five-year veteran is listed as day to day and it is unclear whether he will play in the Lakers' next game on Thursday against the Portland Trail Blazers.
"I'm just trying to get it healthy, get it back right because games come so quick and there's really no time to rest," McRoberts said. "So, I'm just trying to rest it up and be healthy for the majority of the season here."
McRoberts, who was wearing black kinesiology tape on his left foot before the game, said the Lakers' training staff is doing "all kinds of stuff" to reduce the swelling in his big toe.
The Lakers finish the week after the Portland game with the second night of a back-to-back against Golden State at home and then host Memphis on Sunday.
McRoberts' fellow free agent signee, Troy Murphy, took his spot in the rotation.
"We have Troy sitting there, so Troy's minutes will go up," said Lakers coach Mike Brown.
Dave McMenamin covers the Lakers for ESPNLosAngeles.com.