Monaco’s baby-faced “Prince” Pierre Casiraghi claims that a February brawl left his royal chin so badly scratched, he had to go on disability for a month. “So this poor kid who doesn’t work couldn’t work for 30 days,” snarked the defense lawyer for accused jaw-puncher Adam Hock, back in Manhattan Criminal Court yesterday on misdemeanor assault charges from the notorious Battle Royale at the Meatpacking’s Double Seven. “What I think this actually means is that he [Casiraghi] can’t go to a club for 30 days,” quipped the lawyer, Joseph Tacopina. It is not immediately clear what work Casiraghi does, although reports say he’s studying economics and plans to work at his late father’s firm. Hock is accused of clocking Casiraghi and his playboy pals during a fracas that sent a magnum of Grey Goose flying and a gaggle of fashion models scattering. Doctors at New York Presbyterian treating Casiraghi after the brawl described him as suffering a “superficial” skin laceration, Tacopina said. A week later, Casiraghi, the 24-year-old grandson of Grace Kelly, “had his royal doctors check out his royal face,” said Tacopina, who diagnosed him with “face trauma.” Casiraghi’s lawyer, Edward Kratt, insists his client and his physicians are not exaggerating. “I know what the real deal is,” Kratt told The Post. “The injury was serious.” But Hock insists he is the victim of a four-against-one scuffle with the “international bar brawlers.” Hock is accused of clobbering Casiraghi and his pals Diego Marroquin, Vladimir Restoin Roitfeld and Greek shipping heir Stavros Niarchos. “We have evidence of these guys [acting out] in Brazil, Belize and Paris,” Tacopina said. “What happened that night happens all the time. They think Mom and Dad will dig them out of whatever trouble they get in.” Hock is due back in court for a possible pretrial hearing on July 30.