Theo Epstein wasn’t happy with the Cubs’ “sloppiness.”

That was the word the president of baseball operations used to express his displeasure with how the team performed in the first half.

“Mental errors” and “lack of fight” weren’t words many would’ve used to describe the Cubs’ identity since Joe Maddon took over as manager. Especially not when they deployed far and away the most dominant defense in the majors in 2016.

The names might sound the same, but when it comes to what they look like in the field, these aren’t the 2016 Cubs.

Beyond the second-highest error total (68) in the National League, team officials and players agree some of the struggles in the first half stemmed from uncharacteristic “weird” mistakes and lapses, as Anthony Rizzo called it.

And if that doesn’t get cleaned up in the final 2½ months of the season, it’s going to make the road to October more challenging than the last four years.

“If they cut down the amount of pitches pitchers throw per inning by making plays they should make, that in and of itself makes the stat better,” Maddon said Monday. “Inversely, when you make a mistake on a routine play, now this guy has to throw 10-15 more intense kind of pitches based on the situation. It’s all interconnected, and nobody talks about it enough.”

Slipping from the top to middle tier of defensive teams is especially significant for a team without a lot of strikeout pitchers. An extra error here or there can be the difference between a win and a loss.

Take the Cubs’ lone loss since the All-Star break against the Reds on Monday at Wrigley Field, for example. Their two errors in the seventh inning led to a run, giving the Reds a 4-3 lead.

And a missed foul pop-up that should’ve been caught by Rizzo one inning later set the stage for a run-scoring double in a two-run inning.

The Cubs have all talked about the need to clean up the mistakes.

“We’ve been better defensively,” Rizzo said. “We’re all aware of it and making sure we’re making good plays and smart decisions.”

Keeping players sharp in the second half is a big part of Maddon’s philosophy of providing regular rest throughout the season.

But this year’s issues won’t be solved entirely with rest. The Cubs have had to use their second- or third-best player at multiple positions for significant stretches.

Ben Zobrist’s presence in the field is missed. The often-overlooked aspect of his absence is he’s good enough at multiple positions to give Maddon better options when he adjusts in the field.

A domino effect was created when Zobrist went on a leave of absence in early May for family reasons, weakening the team defensively from game to game.

For example, the Cubs haven’t been able to play Albert Almora in center field as often as they expected because of his subpar hitting.

Meaning Jason Heyward, a Gold Glove right fielder, has moved to center more often, where he isn’t as good.

Meaning their best third baseman, Kris Bryant, has played more right field.

Meaning David Bote, a below-average infielder, has had to fill in for Bryant.

Maddon said infielder Addison Russell, who was out with a 40-game domestic-violence suspension, “makes everything look a little bit brighter” in the field.

Maybe more Russell down the stretch will help. Maybe Zobrist will come back.

Or maybe this is just who the 2019 Cubs are.