This is Renteria's first big league managing job, and the 52-year-old has been very positive but also low key about his role.
"I feel pretty calm, quite frankly," he said prior to Friday's game. "I'm not too worried about anything, just got to go play the game. We still have to play the game."
Renteria opened the home portion of the schedule against the Phillies and former Cubs second baseman Ryne Sandberg, who is very familiar with Wrigley Field's elements.
What can Renteria do to change the Cubs, who have four straight losing seasons?
"Hopefully, it's just the mindset," Renteria said. "I'm a pretty positive individual, and I think I try to make sure we understand we have to stay focused and grind out every game and every piece of work we do does matter, every at-bat matters, every out matters, and there's a way to approach the game, win, lose or draw. Hopefully, I bring an attitude that's a fighting attitude and wants to win."
The Cubs may not be predicted to finish high in the National League Central, but Renteria is optimistic.
"For us, not winning is disappointing for any manager or team," he said. "That's the goal. I know if we fall short of that, it'll be disappointing because we want to win and the club wants to win.
"Every club wants to get into the playoffs, and our mindset is to get into the playoffs," he said. "Most people might think that's unrealistic, but these kids here are playing pretty well. We had a decent spring. What do they say? 'Hope springs eternal?' We'll see where we're at when it's all said and done."
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.