(Photo by John McDonnell/The Washington Post)

Two days after Bryce Harper’s head collided with an infielder’s shin, the Nationals continued to monitor him for concussion-like symptoms. Though Harper felt fine Tuesday and told Nationals officials Wednesday he felt no dizziness or nausea, Nationals trainers watched Harper during batting practice and conducted tests following the workout to ensure he could play Wednesday against the Mets.

“Sometimes, concussion-like symptoms manifest themselves 24 to 48 hours after the fact,” Manager Matt Williams said. “So we just have to keep monitoring that and make sure that he feels good before he goes back out there.”

About 15 minutes before first pitch, Harper jogged from the dugout to center field and signaled that he had passed whatever battery of tests the Nationals gave him.

In the second inning Monday, Harper slid hard into second base to break up a double play, and his head smacked off Eric Young Jr.’s shin. Harper writhed in the dirt before walking off the field.

In the dugout, head athletic trainer Lee Kuntz administered a concussion test, and after Harper passed, he returned to the game and remained in the rest of the afternoon. Harper also underwent a second test following the game, which he also passed.

Harper complained of a “pretty bad headache” after the Nationals’ 9-7 win. He also said “I didn’t see stars, and I’ve seen stars before.” Harper did not stop to chat today on his way off the field, but earlier he said he felt fine.