"I started feeling it a couple days ago, I felt it a little bit when we played in Denver," Rosario said. "When I felt it a couple of days ago I felt one area, but yesterday I felt it in another part of the hand. So tomorrow they're going to do an MRI to detail what it is.
"For right now, we feel like it's a bruise. So we're going to work on it, we're going to ice it. Then we'll find out tomorrow what happened."
Rosario said he feels it on swings, especially when he misses. But he said he felt it during a double on Saturday night.
"I don't think it's a DL situation, but we are looking at him day to day here," Rockies manager Walt Weiss said before Sunday's game.
Rosario, hitting .244 with three home runs, five doubles and 13 RBIs in 22 games, was scratched from the lineup April 11 with a left wrist issue. Weiss said this isn't related to that issue, which occurred when he was sliding into a base.
"He's OK, but his hand is pretty sore, though," Weiss said. "He felt it on his swing last night. It's a little tender."
While the Rockies are counting on Rosario not having an extended absence, situations like those are among the reasons the Rockies signed Michael McKenry, who has caught in the Majors for the Rockies and the Pirates. McKenry is batting .310 with two home runs and 10 RBIs in 11 games at Triple-A Colorado Springs.
Thomas Harding is a reporter for MLB.com. Follow him on Twitter @harding_at_mlb. This story was not subject to the approval of Major League Baseball or its clubs.