Melissa Gilbert was absent from Tuesday night's "Dancing with the Stars" results show after being injured during Monday night's performance show.
Host Tom Bergeron announced that Gilbert was not well enough to be in the ballroom after she was taken to the hospital Monday night, People magazine reported.
"Melissa is not here. She did suffer a mild concussion," Bergeron said.
"On her doctor's advice she is taking a rest day and if they get through tonight she'll be able to compete going forward."
The actress, who starred in "Little House on the Prairie" when she was a child, was injured during her dance with partner Maksim Chmerkovskiy.
The two danced to the White Stripes song "Conquest" during the show's Rock Week, earning 22 points for what judge Bruno Tonioli called Gilbert's "best performance by far."
While the injury didn't appear like much to viewers, Gilbert, 47, reportedly began complaining of dizziness backstage.
Fellow dancer Gavin DeGraw carried her out of the studio, where she was placed on a stretcher and taken by ambulance to the hospital.
"She injured herself, and as a precaution she's gone to the hospital to get checked out," Bergeron said on air.
Gilbert was treated at the hospital for whiplash and a concussion.
"I'm alright. Mild concussion and whiplash. Very soon I will be safely home resting and being taken care of," Gilbert tweeted after being treated.
Bergeron asked her partner Chmerkovskiy about his injured arm on Tuesday night's show, with him joking that "it takes away from the pain in the ankles knees and shoulders," before turning the attention back on Gilbert, People reported.
"I really do hope she's OK. She's a fighter, a trooper," he said of Gilbert.
"I'm looking forward to next week. She's looking forward to next week. But she's a little sedated so she doesn't know what she's looking forward to."
Gilbert's absence wasn't the night's only surprise, as 'The View' host Sherri Shepherd was voted off.
"I love this whole experience," said Sherri, fighting back tears.
Len Goodman said all the judges were "in total shock."