PITTSBURGH -- Forget “Embrace the Target” or “Try Not to Suck” or any of the other sayings popularized by Chicago Cubs manager Joe Maddon. The phrase of the season -- as unsexy as it is -- is “run differential.” The Cubs are on a historic pace of blowing teams out, and there’s no end in sight after a dominating sweep of the Pittsburgh Pirates this week.

“We’re superhappy to beat up on our division second-place team and separate ourselves a little bit, but the approach of the team is still day-to-day,” Cubs catcher David Ross said after Wednesday’s 6-2 finale.

That four-run margin was as close as the Pirates came in any one game, and perhaps the Cubs need to keep things day-to-day in order to stay grounded. Usually that cliché is used to keep a team focused, but since the end of spring training, this team has been on a mission.

“We do a really good job of grinding out each individual inning, whether we’re hitting or on defense,” Wednesday’s winner Jon Lester said. “We’ve done a good job so far.”

Lester is part of a starting staff that is turning heads and is a big reason that the team’s winning percentage (.769) and difference between runs scored and runs against (plus-93) are so off the charts. The rotation has a 2.19 ERA after Lester’s 5⅔ scoreless innings. He ground through some of the game, but for the second time in two starts, he escaped a bases-loaded-nobody-out jam -- and the Cubs never looked back. The final tally for the series was 20-5 in favor of the visitors. If you’re keeping track at home, that was another plus-15 on their run differential.

“We know what we’re up against in this division,” Lester said. “[Pittsburgh]'s a good ball club. The Cardinals are a good ball club. We know we have to go through those two teams to go where we want to go.”

At this point, observers might think the opposite is true -- teams have to go through the Cubs -- as the numbers point to a run-scoring and run-prevention pace that is unprecedented in the history of the game. The Cubs have scored 93 more runs than their opponents through the first 26 games. It is the greatest differential through 26 games since 1905 and puts them on pace to shatter the all-time record of plus-411 set by the 1939 New York Yankees. Of course, they’ll slow down, won’t they? If not, they’ll outscore the opposition by a whopping 579 runs over the course of 162 games.

“We pitched really well,” Maddon said. “We’ve been doing that the whole year. We keep having good at-bats, then wear people out at the end. That’s pretty much been the road map to this point.”

First in runs scored, first in runs prevented: The statistics can start and end right there.

Think about it: They’re outscoring American League teams that get to use a designated hitter. Then again, Cubs pitchers have outhit some teams’ designated hitters.

Anthony Rizzo homered and scored three of the Cubs' six runs on Wednesday. AP Photo/Keith Srakocic

One narrative emerging is around the Cubs' ability to plug in backups and not miss a beat. Miguel Montero is down? Let’s catch Tim Federowicz for Jake Arrieta. He was on base three times on Tuesday and amusingly said, "You could put a net back there," in reference to catching the Cy Young winner.

When Jason Heyward surprised everyone with a wrist injury and then Matt Szczur strained a hamstring, the Cubs figured to lose a little something, at least on defense. But here comes Javier Baez, who’s putting on a show at third base and even at the plate.

“Javy continues to play a different level of baseball,” Maddon said. “The whole game. The fact that he’s so mentally aware is fun to watch.”

Maybe this is what it felt like last season for the St. Louis Cardinals. Every time they endured an injury, another guy stepped up.

The Cubs are feeding off each other and having a blast at the same time. Wacky Suit Week might need a return engagement after the team went undefeated in Pittsburgh. As fun as it was, Maddon always tries to provide some meaning in his gimmicks. Players were required to wear at least a part of their zany suits around town, inducing plenty of strange stares. It goes back to Maddon’s essence: being comfortable in your own skin.

“I really believe it benefits you out here,” Maddon said before the game, pointing to the field. “I believe the fact that you’re not concerned about superficial nonsense permits you to focus and play your game better.”

Who can argue with him the way his team is playing? Every button he pushes works and every player on the roster is seemingly contributing. Can they keep it up?

Maybe the Pirates aren’t as good as we think -- they need some help on the mound -- but the Washington Nationals might be the Cubs' equal. They come to Chicago for four games beginning on Thursday, sporting the exact same ERA from their starting staff as the Cubs'. Ross says they’ll think about them on Thursday morning, so for now the they’ll just celebrate a series sweep playing without their most expensive player.

“The fact that we can give Jason [Heyward] some rest and still play well is a good thing,” Maddon said. “Go up and down the lineup -- everyone is contributing.”

But in the end, Maddon wanted to stress one simple thing about the newest favorite phrase of any Cubs fan: The Cubs' run differential isn’t about their offense.

“It says a lot about our pitching,” Maddon stated.

Just ask the Pirates.