BOSTON — Trevor Story is done for the season. Triston Casas is out for at least another month or so. The remainder of the lineup seems to be in a collective slump.

That means the margin for error is slighter for the Red Sox these days. They need good pitching and strong defense to win their share of games as they scuffle offensively. Heading into Tuesday night, the Red Sox were a middle-of-the-pack team offensively (tied for eighth in the league with 175 runs scored).

Suddenly, for a franchise known for big-name sluggers and high-powered lineups, run prevention is the order of the day.

It may not be what he’s accustomed to, but Alex Cora is embracing the challenge.

“Yeah, I believe so,” said Cora Tuesday afternoon. “Even (Monday), you have to make sure to maximize the bench. We were a little bit aggressive there with the lefties, but it’s just because I felt like we had to maximize matchups. Then, we went with the double switch because we needed to save (David Hamilton) as a pinch-runner or in case we needed Reese (McGuire) to pinch hit and we were running out of players.

“It’s been a challenge, but a good one, honestly, to be locked in. It seems like every pitch matters, every at-bat matters. Understanding, too, that those guys in the front (starting pitchers), they’re doing an amazing job. They’re helping us to make decisions late in games because they’re going six or seven innings. It’s been good, just to go toe-to-toe with the opposition and ‘Here’s what they’re thinking,’ and ‘Here’s what we have to do.’ Sometimes it works, sometimes we need to be better.”

Ordinarily, that might involve being more aggressive on the bases. When a team isn’t scoring a lot of runs, they sometimes need to be aggressive and take advantage of every extra 90 feet. But for now, the Sox have scaled back on their stolen base attempts.

“We have to be extremely cautious with a our running game,” said Cora. “At one point, we were getting thrown out too much and that takes away from us. Sometimes, you push the envelope and sometimes, you have to be smart.”

It helps, too, that the defense has tightened up considerably since a highly inauspicious start in that area. The Sox bumbled their way 20 errors and 26 unearned runs in their first 20 games. Since then, however, they’ve committed only 10 errors in the last 21 games, resulting in just four unearned runs in that span.