Instead, the Cubs lost for the ninth time in their last 13 games, and fell to 0-3 against the Mets, who ousted them last season in the National League Championship Series. The problem wasn't just Arrieta, manager Joe Maddon said, but the hitters not coming through in key situations.
"The lack of contact in crucial moments really hurt us," Maddon said.
Of course, there were some questionable calls regarding home-plate umpire Laz Diaz's strike zone.
"It was amorphic," Maddon said. "That's as negative as I'm going to get."
Still, Arrieta has not completed six innings in each of his last three starts. On Saturday, he needed 35 pitches to finish the first, and then settled down, retiring 10 in a row before Asdrubal Cabrera's single with one out in the fourth. Cabrera eventually scored on Travis d'Arnaud's single that Javier Baez nearly caught in shallow center with his bare hand.
Is Arrieta worried? No.
"It's frustrating for me," he said. "I expect a lot more out of myself, and to let it continue for three, four starts is not something that I like to see happen. ... I just need to do a better job of being aggressive early in the count and forcing the issue."
There's no need to over-analyze, Arrieta said.
"It's not a lot to work on," he said. "We're spinning our wheels a little too much trying to figure out what the solution is, or is there a problem? I just need to pitch better, bottom line."
He called his outing an "odd day physically" because his timing was off and he didn't have good velocity.
"If he was injured, I'd be more concerned," Maddon said. "He's not injured. That's the reason I feel he'll be fine."
Arrieta said the changes are simple. He can't let hitters get ahead.
"When I allow hitters to stand in there for four-plus pitches, their job becomes a little easier," he said. "I need to be in more pitcher-friendly counts. That's really the summary from my perspective -- is to get after it a little bit more and force the issue."
Every team and every player has ups and downs during the season. This is Arrieta's down time.
"I don't think there's a big cause for concern," Arrieta said. "Every team, regardless of if you're in first or last place, every team has those spells where you might struggle a little bit and things aren't going as well as you'd expect. From my perspective, individually, it's one of those spells for me.
"I'm resilient, I'll bounce back. I'll get to the point where I was early in the season and last year soon. This won't continue. It's frustrating it has gone for this long of a period. We'll make it right."