The Mets were forced to scratch ace Noah Syndergaard ahead of Thursday afternoon's scheduled start against the Braves.
Manager Terry Collins told reporters Syndergaard is dealing with a "tired arm." The injury is officially being called biceps tendinitis.
Matt Harvey will start in Syndergaard's place Thursday against Atlanta.
Syndergaard, who is off to a fantastic start with a 1.73 ERA and 0.88 WHIP in his first four outings, dealt with blister issues during his first couple of starts this season.
While Syndergaard's arm fatigue doesn't appear to be anything serious right now, it will be something worth keeping an eye on as the season progresses. It is usually not a good sign when a 24-year-old is dealing with a tired arm during the first month of the season.