NEW YORK -- It speaks to Jake Arrieta's recent greatness that Cubs manager Joe Maddon took such note of two pitches during Arrieta's National League Division Series start against St. Louis. One was a hanging slider/cutter to Cardinals shortstop Jhonny Peralta. The other was a backdoor breaking ball up in the zone to outfielder Jason Heyward.
They were the sort of mistakes that dot nearly every pitching performance in Major League Baseball -- unless you're a pitcher on the historic run Arrieta enjoyed after the All-Star break -- and they made Maddon wonder whether Arrieta's personal-record innings total might finally be producing an effect.
Human was good enough to beat the Cardinals that night, with Arrieta surrendering four earned runs for the first time since mid-June in his first non-quality start in 22 outings, and the Cubs' offense picking him up by bashing a postseason-record six home runs.
Whether it was a blip in Arrieta's dominant stretch drive or the first sign of Arrieta bowing from the weight of a heavy workload will become clearer on Sunday, when he works opposite the Mets' Noah Syndergaard. The Cubs are in a 1-0 hole in the best-of-seven series after dropping Game 1 on Saturday, 4-2.
Arrieta will enter the night having thrown 243 2/3 innings since the start of the regular season, 87 more than 2014. This year's count includes 14 2/3 emotion-packed innings in the postseason -- a shutout in Pittsburgh in the NL Wild Card Game, and 5 2/3 more hard-fought innings against the Cardinals in Game 3 of the NLDS.
By tapping Jon Lester for Game 1 of the NLCS, Maddon afforded 29-year-old Arrieta an extra day of rest.
"I'd probably be more concerned if he was 23 or 24, to be honest," Maddon said of the innings jump. "The other part is if you look at his pitches per inning, they're pretty good. He's one of the lower, I think right around 15 pitches per innings pitched, and that's pretty darned good. So maybe he's thrown a lot of innings, but a lot of non-stressful innings, which I do think matters."
The postseason innings have carried a different kind of stress, Arrieta has acknowledged. After blanking the Pirates to send the Cubs on to St. Louis, Arrieta was "exhausted." With each start, he is learning to manage that energy expenditure.
"Throughout the course of the day you start to contemplate your routine and think about the game in different scenarios, and you start to -- that heart rate starts to rise a little bit," he said. "You start to get that anxious energy, that excitement, and I think trying to find a way to relax, and trying to calm that down before you get to the ballpark, because at that point in time, once your routine starts, it's kind of hard to keep the energy level low.
"The physical toll really hasn't bothered me at all, but I think that the mental side of it and all the energy you burn leading up to the game does have a little bit of an effect. But having a couple of these under my belt now, I'm pretty confident going in that I'll be able to handle that pretty well."
This comes after a resplendent regular season. Arrieta won 22 times, most for a Cubs pitcher since Hall of Famer Fergie Jenkins went 24-13 in 1971. Arrieta went 16-1 with a 0.86 ERA over his final 20 regular-season starts, including 11-0 with a 0.41 ERA in August and September/October. That's the lowest ERA over the final two months of a season since they started tracking the stat. Arrieta's 236 strikeouts made him the first Cub to top 230 since Kerry Wood and Mark Prior both did in 2003.
Then came the Wild Card Game, a five-hit, no-walk, 11-strikeout masterpiece.
"That game pretty much taught me, 'Just watch him,'" Maddon said. "The game against the Pirates was different, and we said, 'Let's go and ride him a little further' in that game because of the one-game magnitude of the situation. Just watch him. The other day [against the Cardinals] I thought he was not as sharp, and I didn't see the finish on the pitches, and I thought I'd have to treat him differently than the past 10 or 15 games."
Now Arrieta has an extra day of rest. How will Maddon approach Sunday?
"My plan is to watch, and don't go with any kind of preconceived thoughts, but watch and try to react accordingly," Maddon said.
In the other dugout is Terry Collins, whose Mets are coming off an NLDS win over the Dodgers in which they faced Clayton Kershaw and Zack Greinke. Now comes Lester and Arrieta.
"The mentality," Collins said, "is, 'Oh [no], we've got to do it again.'"
Adam McCalvy is a reporter for MLB.com. Follow him on Twitter @AdamMcCalvy, like him on Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.