PHILADELPHIA -- As Bryce Harper played catch with bullpen catcher Craig Driver before the fifth inning of Sunday's 3-2 loss to the Padres, the Phillies' superstar wasn’t sure what was happening.

There were “little splotches” in his eyes, which he promptly decided were a product of “allergies or something like that.” After Jason Vargas threw a quick 1-2-3 inning, Harper returned to the dugout and put in some eye drops, but the splotches lingered.

Harper’s day was over.

The right fielder was removed from the game with what the Phillies described as dehydration, the result of a humid and muggy 90-degree afternoon at Citizens Bank Park.

“It just wouldn't go away,” Harper said. “I can't really play with vision like that.”

Harper retreated to the clubhouse with the team’s training staff, which diagnosed him and administered an IV. Assistant athletic trainer Shawn Fcasni was seen talking with manager Gabe Kapler in the dugout shortly after Harper left the game.

“We weren't sure what was going on with him, so we took the most precautionary measure we could and got him out of that baseball game,” Kapler said. “I thought our medical staff did a great job making sure that we took good care of him.”

Harper said the blurriness began sometime in the fourth inning, which is staggering given that he threw Austin Hedges out at second as he tried to stretch a single into a double in the top of the frame, then singled off Padres starter Joey Lucchesi in the bottom half.

Having never experienced this particular issue, Harper admitted he was scared once it failed to improve with the eye drops.

“Any time something like that happens, you're not excited about that,” said Harper, who was dealing with only a slight headache after the game. “I feel better now. It's weird. An hour ago, I couldn't see in front of me. Now, I feel fine.”

Harper has been on fire in August, entering Sunday with eight home runs, 18 RBIs and a 1.000 OPS in his first 16 games this month. In 123 games this season, Harper has a .254/.374/.492 slash line with 26 home runs and 90 RBIs.

Despite two straight losses to the Padres this weekend, Harper knows that the Phillies, who entered Sunday just one game behind the Cubs for the second National League Wild Card spot, have a great opportunity ahead of them.

“It's going to be stacked like it is right now all the way until the end,” Harper said. “We just have to keep playing our game, not really scoreboard-watch as much as possible. If we lose, it doesn't really matter. We just have to keep winning, keep doing our thing, not worry about anyone else around us.”

And of course, drink plenty of water.