By MARK HALE

The Mets have a potential issue now as Orlando Hernandez is headed to New York today because of “tightness” in his shoulder, according to Omar Minaya.

The Mets already have Jose Valentin going to New York for an MRI on his right knee — he left Saturday’s game in the fourth inning — but El Duque is now the bigger concern. He’s a critical pitcher on the team and is off to a great start. Minaya said the 41-year-old Hernandez just felt the tightness today. He had thrown a bullpen session yesterday.

During spring training, Hernandez had a multiple ailments, including neck arthritis and a right hamstring cramp.