Solano was back in the starting lineup on Monday in the series opener with the Nationals.
Adeiny Hechavarria, who celebrated his 24th birthday on Monday, has started every game this season at shortstop.
Both lack much experience. Solano has 106 games in the big leagues, and Hechavarria is at 54. Both have already gone through some growing pains this year. So manager Mike Redmond is checking on them to see if mental fatigue sets in.
"It's hard to play every day in the big leagues," Redmond said. "It's the mental and physical preparation every single day. It's tough facing big league pitching. You never get a break. We've got to keep an eye on him."
Sometimes an off-day, like Solano had on Sunday, can help players refresh themselves.
"It's more of a mental day, just to kind of recharge your batteries," Redmond said. "I know as a player, when I played a lot, sometimes you just need it."
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter