Former Calvin Klein boy toy collared for penthouse beatdown.

Calvin Klein’s former boy toy was busted in his Greenwich Street penthouse early Tuesday after he allegedly punched another man in the face, sources said.Nicholas Gruber, 22, was hanging out in his luxury pad with the 20-year-old man before the fight broke out about 4:20 a.m., the sources said.“It’s really unfortunate,” the victim told the Daily News over the phone. “I thought he was a good friend. I’m OK for now, but I don’t know about the future.”After the brawl, the injured man thought about going home, but called the police instead.“Blood was coming out of my face,” he said.Cops soon arrived, but Gruber flailed his arms to avoid getting cuffed, sources said. As the officers wrestled the model and former flame of fashion designer Calvin Klein, he was spotted trying to shove something in his pants, sources said.When the officers searched Gruber at the Sixth Precinct stationhouse, they found what appeared to be cocaine stashed in his underwear, sources said.He was later charged with assault and criminal possession of a controlled substance.