Mets pitcher Orlando Hernandez has arthritis in his neck and will be sidelined for three or four days after receiving a cortisone shot. El Duque, slated to be the No. 2 starter in the Mets' suspect rotation, left spring training Thursday and returned to New York to have his neck examined. He underwent an MRI, which did not show any disk problems, general manager Omar Minaya said. "Everything looks well," Minaya said on a conference call. "It was just good news. It was preventive, and we feel really good -- especially after reviewing the MRI."