Whitfield was diagnosed with non-Hodgkin lymphoma about 18 months ago, and had been battling the disease since then. He had hoped to return to 'Spartacus' for the show's second season, but a recurrence of his illness prevented that.

Eventually he had to leave the role entirely, and, after Starz made the prequel series 'Spartacus: Gods of the Arena' (in which Spartacus did not appear), Australian actor Liam McIntyre was eventually cast in the lead role of the next season of the show, 'Spartacus: Vengeance.'

"We are deeply saddened by the loss of our dear friend and colleague, Andy Whitfield," Starz president and CEO Chris Albrecht said in a statement posted on the show's Facebook page Sunday. "We were fortunate to have worked with Andy in `Spartacus' and came to know that the man who played a champion on-screen was also a champion in his own life. Andy was an inspiration to all of us as he faced this very personal battle with courage, strength and grace. Our thoughts and prayers are with his family during this difficult time. He will live on in the hearts of his family, friends and fans."

"Andy, you will be missed and forever in our hearts," 'Spartacus' writer Maurissa Tancharoen tweeted Sunday. "The news we hoped we'd never hear," added director Michael Hurst. "So much sadness. RIP."

Update: Co-star Lucy Lawless has released a statement to EW. It read, in part: "He was a gentle man who never said a bad word about anyone, a gifted photographer, engineer (no really!) and a brilliant actor. Andy's incandescent film presence made men want to be him and women want to marry him."

At Comic-Con in 2010, Whitfield had just been through a treatment regime and he thought he'd still be returning to the show. He got a hero's welcome from fans, who had vociferously expressed their support for him since the news of his illness broke earlier that year. Their vocal support on web sites and in San Diego came as no surprise: Whitfield had grown as an actor before our eyes in that first season. His Spartacus was a compelling and charismatic man, one who grew more complex and driven as the season wore on.

I was lucky enough to sit down for a one-on-one interview with Whitfield at that Comic-Con, and he struck me as a thoughtful man, one who was serene, engaging and positive, despite all he'd been through. He had that typical Australian mischievous sense of humor, but there was a serious energy about him as well. He talked about feeling "a fearlessness I never had before." I had very much hoped to see him return to the work he loved and share all those qualities with us once again. Today's news is very sad indeed.

I'm sure I speak for all 'Spartacus' fans when I say that our hearts go out to his family and friends.