"His on-base percentage has been extremely high, especially against right-handed pitching," Renteria said of Valbuena, who has a .420 on-base percentage against right-handed pitchers. "Yesterday, I think he set the tone. He fouled off a lot of pitches and got on base."
The Cubs have used Emilio Bonifacio and Junior Lake so far this season in the No. 1 spot. Valbuena has been used primarily against right-handed pitchers, and he could be inserted more at the top of the lineup.
"He grinds out at-bats," Renteria said.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. Teddy Cahill is a reporter for MLB.com. Follow him on Twitter at @tedcahill. This story was not subject to the approval of Major League Baseball or its clubs.