Updated: May 5, 2014 11:28PM
Only 24, first baseman Anthony Rizzo is still finding himself.
If he keeps having success, manager Rick Renteria said Sunday, Rizzo could help prospects do the same.
Renteria said the success of Rizzo and other Cubs “gives them more and more confidence to be able to carry that persona” and help other prospects whenever they make it to Wrigley Field.
“To be able to communicate with younger players when they come up,” Renteria said, “that’s one of those things that helps them.
“If they have success, they have something to lean on and base their ability, and it gives them credibility when they want to talk to younger players.”
Rizzo, he said, is “taking care of business right now,” having entered the game Sunday against the Cardinals with a .421 on-base percentage, fifth-best in the National League.
“He’s just growing up,” Renteria said. “I know he worked very hard over the winter, worked very hard in the spring.
“I think he’s making a tremendous mental adjustment as to how he wants to approach pitchers. [He] kinda knows what they’re trying to do with him.
“All those things come with maturation and growing and learning through his experiences.”
Chris Coghlan’s Iowa Cubs manager didn’t try to hide the news Friday.
“He was like, ‘Go in the office, but you know what I’m gonna say,’ ” the former NL Rookie of the Year said.
He was no less thrilled to get the call to make his Cubs debut, having played five seasons with the Marlins before starting this one with Iowa.
“It’s humbling to go down to Triple-A, but it was also good at the same time because you can go down there and play every day,” he said. “You get at-bats under your belt, then try to kick down the door once you get up here.”
One day after going 3-for-3 with a two-run home run, Junior Lake didn’t start against Lance Lynn.
Renteria said he wants to put his young players in the best position to succeed, and that means playing a better matchup sometimes. Left-handed-hitting Ryan Kalish started instead.
Renteria said he has talked to Lake — who’s 6-for-13 against the Cardinals with two homers this season — about the approach.
“We continue to chip away and make sure that we give them the best opportunity to feel more and more confident,” he said. “I think that, as the confidence continues to grow with the success that they have, it starts to eliminate over time sitting them against certain guys. You just continue to play them.’’
◆ As part of Wrigley Field’s centennial, the teams saluted the 1920s. Both wore throwback uniforms, the Cubs donning a wishbone ‘‘C’’ jersey from 1929. Entering Sunday, the Cubs were 6-2 all-time when wearing retro uniforms in regular-season games.
◆ The Cubs used six pitchers Saturday, the most for a nine-inning shutout in at least the last 100 years of franchise history.