The 46-year-old actor also opens up about whether he'd reprise his role as Deacon Frost.
Dorff played Blade's nemesis, Deacon Frost, in the 1998 movie starring Wesley Snipes. It was announced at San Diego Comic-Con last July that the Marvel vampire hunter franchise was being rebooted with Ali in the title role.
"I saw him after it was announced [at Comic-Con 2019] and I'm happy for him. I think he'll do a great job with Blade and reinventing the franchise," Dorff exclusively told ET while promoting his new Fox series, Deputy, at the Television Critics Association winter press tour on Tuesday. "It probably should've been done a while ago, but I think it's good for him."
Dorff said he and Ali haven't talked "too much" about Blade. "But I mean, I love the guy. I'm sure he'll do it justice. To have such a great actor in the part of Blade for this new generation, it'll be great," he shared.
"We talked about doing a Deacon Frost movie on its own at one point, me and the director of the original Blade, who is just a genius, Stephen Norrington, and it never really happened because Marvel was a new entity and Kevin Feige was kind of building this whole new universe he's built successfully," Dorff explained when asked about reprising his role. "They weren't really interested in the dark Marvel movie but maybe after Joker and all this stuff, maybe it'll start to be trendy."
The 46-year-old actor isn't sure whether he'd return for Ali's Blade, but would be open to starring in a Deacon-focused movie.
"I definitely would love to reinvent that character because that character's someone who really stands [the test of time]. I still talk about [him] 20-something years later. I'm still signing Deacon Frost pictures out front today, so we'll see where it goes," he told ET.
"I'm not the biggest fan of the superhero genre myself, but I did really love what my friend, Joaquin [Phoenix], did in Joker, and I think he's probably going to win the Oscar for that. I'm really proud of him for his work in that, and I think there is room to tell other stories. I'm just not a big fan of the big ensemble, like 50 characters in one movie frame, it's just a bit much for me," Doff added. "But then again, I'm 46 and I'm old. I'm not a kid anymore so if I was a kid, I'd probably love it."
Snipes shared his congratulations to Ali after news broke of his casting in July.
"Congratulations and Salaam to Mahershala Ali, a beautiful and talented artist whose expressions I look forward to experiencing for many years to come," he said in a statement to Comicbook.com. "Inshallah, we will someday work together."
"Most importantly to my loyal fans, the incredible outpouring of love is overwhelming. I am grateful for the never-ending support," Snipes added. "So, 'nah fret nah worry, it's not de end of de story.' Welcome to the Daywalker Klique."
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