In the top of the third, Hamilton crashed into the center-field wall after just missing a leaping catch on Martin Prado's fly ball. He appeared to be rubbing his right shoulder after Prado reached third base with a triple.
"He went into the whole side of his body. His slammed into it," Reds manager Bryan Price said. "His shoulder was fine but his neck was a little bit [sore]. It was more than the fact he had the contusion on his knee. That was the most prominent, but he had other areas that made contact with the wall that had some physical repercussions in a lost battle with the outfield wall."
That play came two innings after a nice running catch for the second out of the first when Hamilton robbed Marcell Ozuna of a potential extra-base hit. He also made contact with the fence, but not as hard.
"When he ran into the chain link, it actually wasn't as bad as when he ran into the padded portion of the wall," Price said. "He hit that a lot harder. Just really almost an entire side of his body has a massive contusion -- from his shoulder down to his knee and so on and so forth. He'll ice it a lot and see how he is [Tuesday]."
Hamilton was replaced by Tyler Holt from a Reds bench that was already taxed with regulars Brandon Phillips and Zack Cozart out of the lineup Monday with minor injuries.
Hamilton's collision has happened during the best stretch of his season. He is batting .264/.318/.362 with a Major League-leading 51 stolen bases overall. But in his past 26 games, he has 28 steals while also raising his average from .237.
Always willing to do what it takes to make a play, and often spectacular as a result, Hamilton has also been injured a few times the past few seasons. He missed the last four games of 2014 with a concussion from a wall collision and one year ago, tore the labrum in his right shoulder making a diving catch. In June, he suffered another concussion while diving into third base and also suffered a facial bruise when he was hit in the head by a fly ball while trying to make a catch.
The effort is appreciated by the pitchers Hamilton plays behind.
"I don't see how you couldn't," Reds starter Brandon Finnegan said. "That guy's a Gold Glover out there. He deserves it. He's played great all year. Having someone with that kind of speed in center field takes a lot of pressure off you."