St. John’s star forward Anthony Mason Jr., who has been plagued by injuries his entire career, suffered another setback when he aggravated a hamstring injury this past weekend. Mason will be out 4-6 weeks, the Post has learned.

The hope is that through rehab the injury will heal sufficiently, but ask any Mets fan (Jose Reyes) or Giants fan (Aaron Ross) about hamstrings and they’ll just cross their fingers.

Mason missed almost all of last season after recovering from surgery to repair a torn tendon his right foot. He has been hampered by ankle injuries as well, limiting his playing time in prior seasons.

“We’re disappointed for Anthony, because we know he wants to be out there,’’ St. John’s coach Norm Roberts said in a statement. “We have to give him time to recover so when he joins us on the court, he’ll be 100 percent.’’