DENVER — With theories flying about why the Cubs remain stuck in a middling start nearly a quarter into the season, manager Joe Maddon sees no issues with attitude or approach.

“I sense sleep deprivation more than anything,” he said before the Cubs fell 3-0 to the Rockies on Wednesday to drop to 17-17. “I think right from the beginning of the year our schedule’s been kind of awkward. Nobody’s really had a chance to settle in.

“I don’t think anybody’s taking anything for granted. On the flip side of that, I’ve always said I love the word ‘expectations,’ and I do. But understand it’s going to be a different path this year. It is. It just has to be.”

Of course, it already has been. At this point in the season, last year’s team was 26-8 on the way to 103 wins. Even the Cubs’ 2015 playoff team, which didn’t start as well, was 19-15 at this point, on the way to 97 wins.

The Cubs’ MLB-high third ‘‘Sunday Night Baseball’’ appearance this past week turned into an 18-

inning game followed by a rainout Monday, a day-night doubleheader Tuesday and another, 50-minute rain delay Wednesday.

“To this point we haven’t pitched nearly as well as starters,” Maddon said. “And the biggest thing for me is defense. We haven’t caught the ball with the regularity that we normally do.

“Those are our bedrocks of our stability of our performance.”

NOTES

— The Cubs plan to call up right-hander Eddie Butler from Class AAA Iowa to join the rotation Friday in St. Louis.

Butler has a 1.17 ERA in five starts for Iowa and takes the place of lefty Brett Anderson, who’s on the disabled list (back).

— Shortstop Addison Russell was scratched from Wednesday’s lineup because of shoulder soreness that bothered him the past week. He’s to be evaluated again Friday.

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