It was a scary sight for the over 4,500 fans that had come to see rehabbing-slugger Ryan Zimmerman take the field with star prospect Bryce Harper on a warm Sunday afternoon in Hagerstown.

But when the first pitch of Harper’s first at-bat of the game againt the Greensboro Grasshoppers came low and inside and struck him in the left knee, even Washington Nationals’ principal owner Mark Lerner, who was seated behind home plate, later admitted that he cringed.

Hagerstown Manager Brian Daubach said Harper’s injury looked like a bruised left knee. No MRIs or X-rays were scheduled, he said, and the Suns would take another look Harper’s knee on Monday morning.

“The medical staff is looking at it now and I’m sure its nothing now,” Daubach said, “but we will reevaluate when he gets back in the morning.”

After he was hit, Harper fell fell back and to the ground. As a trainer and Daubach came to check on him, Harper grabbed his feet with his arms, seemingly trying to stretch his legs.

But when Harper got up, the left-handed hitter struggled to stand and hobbled to the dugout. It appeared that Harper, known as a full-throttle, aggressive player who crashes into walls to make catches, didn’t think he play any more.

“It must have really hurt for him to pull himself out of the game,” Lerner said during the game. “But I would guess he’ll be back tomorrow night. He could probably come back into the game if they would let him.”

Following the inning, Harper, who was not made available to reporters after the game, walked from the dugout to the clubhouse without a noticeable limp.

Later in the game, Harper seemed relaxed seated with his teammates just outside the clubhouse with a wrap around his knee while dressed in street clothes and donning black sunglasses.

“He’s good,” Zimmerman said of Harper. “He’s fine. I think it was more precautionary.”