ST. LOUIS – The price of perfection is the pain that comes with mediocrity. Because Jake Arrieta is intimately familiar with the former and ill-acquainted with the latter, and because baseball delights in humbling even its demigods, a day like Wednesday was inevitable. Jake Arrieta, superhuman pitcher, would be mere mortal for one afternoon. And, it turns out, that was OK.

"Picked a pretty good day to be [expletive]," he said.

Welcome to life with the Chicago Cubs, where the best pitcher on the planet not named Clayton Kershaw can put up his first mediocre regular-season outing in, oh, a year and his teammates respond by pummeling the pitching staff of their bitter rival for a second consecutive day. The 9-8 victory Wednesday over the St. Louis Cardinals wasn't pretty. Considering the previous week, they weren't terribly concerned about aesthetics.

In the course of it, with six losses in eight games, the Cubs showed they were indeed corporeal, and that wee mite of doubt about their long-term viability showed up just to say hi. As they've done with everything in their path, the Cubs proceeded to pull out a size-20 boot and stomp it to nothingness, first with a convincing win Tuesday against the Cardinals and then showing Wednesday they needn't Arrieta at his Cy Young best to win.

View photos The Cubs have won Jake Arrieta's past 23 starts. (AP) More

Gone was his MLB-record streak of 29 consecutive starts allowing three runs or fewer; he made the sin of allowing four. Extended was his streak of 23 consecutive starts won by his team, tying the MLB record held by Kris Medlen over three seasons' worth of starts. Arrieta is now 9-0 this season. His ERA is 1.72.

"He's 9-0 and he's been struggling a bit," Cubs manager Joe Maddon said. "That's not bad."

Struggles are relative, of course. Most teams in baseball would love to struggle like the Cubs, who are now on pace for only 112 wins after ending a streak that had seen them lose their previous 14 getaway-day games in St. Louis. They've scored the third-most runs in baseball. They've allowed the fewest. They've drawn 25 more walks than every other team. Opponents are hitting an even .200 against them. They don't hit into double plays. Their third baseman has improved his strikeout rate by more than 50 percent. Their second baseman might be the hottest hitter in baseball at the moment. They're so good their closer rarely gets to, you know, close. And so when Arrieta throws up a stinker – or at least a stinker for him, seeing as there have been more than 300 starts this season worse than Arrieta's five-inning, seven-hit, four-run, one-walk, four-strikeout line Wednesday – they're equipped enough to shrug it off.

"He's not going to throw up zeroes every time," Cubs third baseman Kris Bryant said. "We realize that, and I think he does, too."

Certainly Arrieta realizes it. That doesn't mean he accepts it. One need only see the resplendence of his beard to intuit the perfectionism that guides Arrieta. Seriously, look at that thing. It's glorious. The only shock is that he carves hitters up every bit as well as he does facial hair, and it's a testament to the Cardinals' lineup that they took decent pitches from Arrieta and managed to do damage. It was the second straight game the Cardinals got to Arrieta, after they touched him up for four runs in Game 3 of the National League Division Series.

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