Academy Award-nominated actor Michael Clarke Duncan is in intensive care at a Los Angeles hospital after going into cardiac arrest, TMZ is reporting.

Duncan, who nabbed an Oscar and a Golden Globe nomination for his work in 1999's "The Green Mile," went into cardiac arrest in the early hours of Friday morning (July 13); TMZ reports that if his girlfriend, reality star Omarosa Stallworth, had not acted so quickly, he may have died.

Stallworth -- who first came to pop-culture prominence on the first season of Donald Trump's "The Apprentice" in 2004 -- discovered the 54-year-old Duncan in a state of cardiac arrest right before 2 a.m. After Stallworth found the actor, she performed CPR on him and was able to resuscitate Duncan until paramedics arrived on the scene. The actor was then transported to a nearby hospital and was admitted into the ICU.

TMZ reports that Duncan's heart rate is now stable and doctors are performing tests to figure out why his heart stopped.

Duncan's rep, Joy Fehily, told various news outlets: "According to doctors, Michael Clarke Duncan suffered a myocardial infarction early this morning. He is now stable, and we look forward to his full recovery."

In addition to his breakout role in "The Green Mile," Duncan also has appeared in "Sin City," "Planet of the Apes," "Armageddon" and "Talladega Nights: the Ballad of Ricky Bobby." When MTV News caught up with him a few years ago, the actor expressed interest in making "Sin City 2" -- if it ever gets off the ground. "I'd love to come back as Manute," he said in 2009. Working with Robert Rodriquez was really cool. He's the type of director that goes around playing his guitar all day, he doesn't holler, he doesn't fuss, he doesn't fight. He's a real mellow director."

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