Selma Blair on Ditching Her Cane in 'Dancing With the Stars' Debut: 'I Am a Vulnerable Person Now' (Exclusive)

By the end of her heartfelt performance, the actress had audiences both in-studio and at home in tears. 

Selma Blair stole the spotlight on Monday night's Dancing With the Stars season premiere, dancing the Viennese waltz with Sasha Farber and, poignantly, handing off her cane amid her ongoing battle with multiple sclerosis (MS). By the end of her heartfelt performance, Blair had audiences both in-studio and at home in tears. 

"It means everything," she tells ET's Matt Cohen of the moment she ditched her cane to lean on Farber, instead. "I am a vulnerable person now out here, you know, with some differences I have or weakness. I really never thought I would be able to dance, like, with both my feet." 

Blair continues to say that it "means so much to be able to lean on someone for my balance," crediting her partner with providing a sense of stability physically and emotionally. "It's such a joy and I hope that we can all see that we can do things out of our comfort zone and it might not look like everybody else, but it's still an incredible feeling."

While Farber left the ballroom quickly after the show to have a root canal ("He was in a lot of pain today and he rushed off to get something taken care of," Blair says) -- the 50-year-old actress credits him with convincing her to join the competition this season. Outside of the show, the two had become friendly as neighbors. 

"Oh gosh, I just thought there was no way I would be able to keep my calm enough to have control over my body and just knowing Sasha a little bit, he's seen me blowing my leaves in the front yard," she says, "I'm like, 'Nope. No, I don't dance. You don’t understand. ... But then we just kind of stood next to each other and he said, 'You know, 'I’m not gonna let you go.' And I said, 'Wow, no one’s ever said that to me before. So I’m gonna go.'"

Blair says she wanted to keep herself active for her 11-year-old son, Arthur Saint Bleick, who joined her backstage at the taping during her interviews. 

"I thought it was amazing," he tells ET. "I’m really happy that she got out and, like, did all of the dance stuff and classes and stuff like that, and now she got in the third-place tie. I thought that was amazing."

For Blair and Farber's "Time of My Life" routine, they scored sevens across the board for a grand total of 28. 

"It was incredible," Blair gushes. "This was a time of learning, to really build my stamina. I was doing great, really in great recovery after a stem cell transplant bone marrow, and I needed to find a way -- I realized I was, like, kind of going backwards a little bit. Not really getting myself moving as much. ... I was like, 'Well, I better build my stamina.'"

"I’m gonna learn to settle into just gratitude and being kind to myself," she concludes. "'Cause everyone has been so kind to me and this feels so good to move, it feels so good to gain strength. I’m just truly, truly grateful and enjoying this so much." 

Dancing With the Stars streams live Mondays at 8 p.m. ET/5 p.m. PT on Disney+ in a new modified, commercial-free format that gives more time for the dances and the judges' feedback. Returning host Tyra Banks is joined by new co-host Alfonso Ribeiro -- as well as returning judges Carrie Ann Inaba, Len Goodman, Derek Hough and Bruno Tonioli.