CHICAGO -- The run will be in the runs. That has been a constant refrain from Cubs manager Joe Maddon throughout this season -- the meaning being that Chicago's rise up the standings will come when the offense finds a consistently high level of performance.

The Cubs have been waiting for months for that run to arrive. Every time it looks as though a corner has been turned, there is another drought waiting around the bend. The latest downturn has come at the most detrimental of moments, with Chicago in desperate need of victories to chase down a spot on the October stage.

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In a 2-1 loss to the Cardinals on Friday afternoon, a game that began with a strong rise-to-the-occasion outing from rookie Alec Mills, the Cubs' offense went quiet again. The loss dropped Chicago five games back of the National League Central-leading Cardinals with eight games left on the Cubs' regular-season slate, including five more between the rivals.

"We are running out of time," Maddon said. "And to catch them is becoming more difficult, but there's still a solid opportunity to be a playoff team. But you've got to keep playing the game as though you're going to catch St. Louis. You've got to go out there with that attitude."

According to Fangraphs, the loss dropped the Cubs' chances of winning the division to 3.3 percent, and the team's chances of capturing a Wild Card spot slipped to 26.6 percent. With the loss, Chicago slipped to two games back of the Brewers for the NL's second Wild Card spot.

Cubs first baseman Anthony Rizzo said the last thing the players need to do right now is think about the various scenarios at play.

"It's not going to be easy," Rizzo said. "But you can't think about what's going to happen and the different outcomes. You've just got to come in tomorrow and win. That's what we'll be focused on doing."

Mills -- am emergency replacement for sidelined starter Cole Hamels (left shoulder) -- gave the Cubs 4 2/3 shutout innings after spending this month in the bullpen. The right-hander struck out six, scattered two hits and received a standing ovation from the Wrigley Field faithful when he headed off the mound in the fifth following an 81-pitch effort.

"Outstanding. Outstanding," said Nicholas Castellanos, who collected his 57th double of the season in the fifth inning but did not score.

The problem was that St. Louis righty Michael Wacha and the Cards' bullpen found ways to subdue Chicago's lineup. The Cubs had their chances -- they loaded the bases in both the third and seventh innings, for example -- but the lone breakthrough came via an error-aided, run-scoring chopper off the bat of David Bote in the second.

In the eighth, Kyle Schwarber tried to ignite a rally by dropping down a well-executed bunt up the third-base line for a leadoff single. One pitch later, Willson Contreras grounded into a double play -- one of four on the day for the Cubs. Those were runners erased. Overall, Chicago stranded nine baserunners and went 1-for-9 with runners in scoring position.

So, when Yadier Molina delivered a two-run single in the sixth, that proved to be enough to take down the Cubs.

"It's weird," Rizzo said of the lineup's recent cold spell.

Aside from a three-run outburst in the ninth inning on Thursday night, the Cubs have managed just six runs in 37 innings over the past four games. That comes after Chicago shattered a slew of records with a 55-run, 14-homer outpouring in the previous four games against the Pirates and Reds. At the time, it looked like the lineup had turned the corner again.

In the four games heavy on offense, the Cubs hit .393/.478/.780. Over the most recent four games, the team's slash line dropped to .179/.247/.291 with nine runs total. Chicago has a plus-33 run differential in those eight games, but a 4-4 record to show for it. The drastic swings make the run differential misleading, and the same could be said for the plus-113 mark on the season as a whole.

The dramatic peaks and valleys -- the Cubs have 21 games with 10 or more runs scored and 21 with one run or fewer this year -- have hindered the club’s ability to separate itself from the pack of playoff hopefuls.

"I've been saying it kind of all year, that the run's going to be in the offense," Maddon said. "We have to somehow get more consistent offensively. When the opportunities come up, we have to take advantage of it. We've had some good at-bats in those moments without any kind of luck, but we've got to figure it out."