Johan Santana has suffered a probable re-tear of the anterior capsule in his left shoulder and a repeat surgery is a "strong possibility."
Santana needed 19 months to throw a Major League pitch after the first procedure, which had been performed on fewer than a dozen pitchers in major league history.
He is in the final guaranteed season of a six-year, $137.5 million deal with the Mets.
Via Adam Rubin/ESPN