Severino, 27, was making his second rehab start following Tommy John surgery in February 2020, pitching for High Class A Hudson Valley against Brooklyn.
Severino began to hobble quickly after throwing a pitch in the second inning. He limped behind the mound, struggling to put weight on his right leg. Coaches and a trainer had to help him off the field.
Severino looked sharp in his first rehab appearance, reaching 98 mph with his fastball. He pitched 1 2/3 innings Saturday, allowing a run, a hit and a walk while striking out three.
New York had hoped Severino could return this season to solidify a rotation led by Gerrit Cole. A two-time All-Star, Severino won 19 games in 2018 and signed a four-year, $40 million deal before 2019, but he has thrown just 12 big league innings since due to shoulder and elbow injuries.