That's one way to fly under the radar.

A heavily bearded Russell Crowe headed out to lunch with his kids in his native Sydney, Australia over the weekend. The recently slimmed-down Les Miserables star, 48, was barely recognizable underneath his facial hair, baseball cap, track pants and black sweatshirt. (The beard is reportedly for his role as Superman's dad, Jor-El, in the upcoming Man of Steel.)

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Since last summer, Crowe has gotten serious about shedding the weight he had gained over the past several years. The actor regularly tweets about his workouts -- and admits when he feels like he's slacking off.

On Monday, the Oscar winner tweeted that he was frustrated after injuring his hamstring at his son's field day, just a few hours after a particularly intense gym session.

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"Total Dad cliche today. Did hammie at youngest's athletic carnival," he wrote. "After a 16 km bike ride, stretches, yoga, air squats and pushups. Oh, the indignity!"

Crowe has two sons, Charles, 8, and Tennyson, 6, with his wife of nine years, Danielle Spencer.

This article originally appeared on Whoa! Slimmed-Down Russell Crowe Is Unrecognizable With Long Gray Beard