By Bruce Levine–

CHICAGO (CBS) — The offense has supplied the best run differential in baseball, and the defense has been tight. Both areas noted, it’s been the Chicago Cubs’ starting pitching that has put the team on top of their division and makes them arguably the top team in all of baseball.

“Our goal is to get to 1,000 innings from our starters,” manager Joe Maddon said. “Any time you suck up innings from your starters makes a huge difference. I have had five starters go 200 before. It is really nice, and normally when that does occurs, you have a well-rested and good bullpen.”

Maddon’s starters have the best ERA in baseball at 2.52. The entire pitching staff ERA of 2.67 also leads the pack of 30 clubs.

Length in starters’ innings and an efficient, if not star-studded, relief corps have given Maddon an abundance of latitude on a daily basis. He can match up and gain an late-inning edge with a fresh group of power arms and finesse pitchers.

Starters Jason Hammel and Kyle Hendricks have taken big strides in earning a chance to go deeper in games. The latest proof of that was a complete game from Hendricks on Saturday. This was the staff’s only complete game of the season other than Jake Arrieta’s no-hitter in April.

“Sometimes your pitcher in the game has a lead and is not throwing well. I won’t just let the lead go away, based on the five-inning rule,” Maddon said, referring to getting at least five innings in for the starter so he’s eligible for a victory. “I am not concerned if he gets a win. It’s about the Cubs getting a win.”

Maddon said he learned the opposite lesson as a young manager in the minor leagues, as he referred to a pitcher cruising through seven innings and then taking him out.

“We gave up that lead in the bullpen, so you learn that opposite lesson as well,” Maddon said. “A 4-0 lead yesterday with Kyle in there was a perfect spot to test him pitching the entire game. He did just that.”

For Hendricks and company, they’ve learned to be teammates first and arrogant starting pitchers second.

You always want confident starters who want to stay in a game. Still, by Maddon’s teachings, you better understand the concept of winning the game before your personal goal of staying in the game, regardless of the quality of your stuff.

“This manager and this team are about winning that day,” Hendricks said. “I have taught myself the mentality of going deep into games. At the same time, it all depends on the situation. If it’s a 1-1 or 1-0 and my spot is coming up in the batting order, I am probably going to get hit for. With the quality guys we have in our bullpen, you just have to understand that. There is not much let-down with those guys. At the same time, wanting to go late in games, Jason and I both want to stay in the games late and want to do it more. We are still proving we can go seven and beyond and still make really good pitches.”

Executives Theo Epstein and Jed Hoyer continue to look for bullpen help. A lockdown left-handed setup man would be the ideal addition to the current quality bullpen.

Hoyer told the media in St Louis last week the club is actively seeking pitching.

Like every contender, the Cubs will look at Yankee setup man/closer Andrew Miller. New York has both Miller and Aroldis Chapman as potential studs to move for younger, almost major league-ready prospects.

The Yankees’ latest resurgence really might only delay the inevitable rebuild the Bronx Bombers must undergo in the next few seasons. Big contracts to Alex Rodriguez, Mark Teixeira, Carlos Beltran and CC Sabbthia will be coming off of the books in the next few seasons.

The Cubs might have the best matchup of minor league talent to extract Miller from the Yankees. That reality will depend on when New York general manager Brian Cashman gets ready to deal.

Bruce Levine covers the Cubs and White Sox for 670 The Score and CBSChicago.com. Follow him on Twitter @MLBBruceLevine.