But Rios didn't anticipate he would be 4-for-38 (.105) with zero RBIs entering Sunday's rainout against the Cardinals since his return.
"I was expecting a little bit of struggle," Rios said. "I was out for a month and a half. That's a long time in season. And coming back at full speed, it can be challenging.
"But I think that we're trained to go through these things. It is frustrating because I'm not performing up to my standards and I'm not helping the team win.
"But I'm fighting through it. I'm very optimistic that it's going to be gone soon."
Rios is not blaming his injury, though he still does feel discomfort in that left hand.
"There's still discomfort in certain situations," he said. "It could be on a missed swing or one with contact. It's hard to pinpoint. But I'm able to play."
The bigger issue beyond Rios' slump is the team's offensive slump. Over the last 12 games entering Sunday, the Royals had a .254 on-base percentage -- that's the worst in baseball.
"Sometimes that happens," Rios said. "It's such a long season, you're going to see all kinds of things happen. Sometimes you'll see all guys struggle. Sometimes you'll see two or three guys carry you.
"But I don't believe for a second we're in a bad spot. I think this team has a lot of talent offensively and and defensively. We're going to do some damage.
"[The offensive slump] is noticeable, that's for sure. But I don't doubt for a minute that anything can spark our offense back. But I don't see any reason for panic."
Jeffrey Flanagan is a reporter for MLB.com. Follow him on Twitter at @FlannyMLB. This story was not subject to the approval of Major League Baseball or its clubs.