The Red Sox must have decided they weren’t going to show the Astros their best stuff. How else do you explain a horrible night in which Eduardo Rodriguez became the fourth straight Sox starter to pitch poorly?

First it was Drew Pomeranz, then Chris Sale, then Rick Porcello, and Thursday night it was Rodriguez.

Not the greatest time for this to happen. All the Red Sox want to do is clinch the American League East title, and they have to do it against the team they might face in the playoffs. This is a weird set of circumstances that hasn’t happened very often.

So, how do teams approach this? Probably not the way the Red Sox started this series.

“We’re going to try to win,’’ Astros manager A.J. Hinch said prior to Thursday’s game. “I know there’s a lot at stake, there’s a lot of familiarity that’s going to happen over the next four days. We don’t know what’s going to happen at the end of the weekend. We need to get our guys ready for the playoffs. We might play these guys, we might not. If the weekend presents itself where it’s a little clearer picture for us or for them or for anybody else, then maybe things change. But I think tonight, you’re seeing both lineups are really good, both pitchers are in the rotation that are going to pitch, I think the bullpens will be used the same.

“There’s a lot of baseball to be played over the next four days.’’

Both teams have reason to go all out. The Red Sox still need to clinch the division. The Astros entered Thursday a game behind the Indians for the AL’s best record. They want to have home-field throughout the playoffs. So this may play out for a day or two.

The Astros’ No. 1 and 2 starters, Justin Verlander and Dallas Keuchel, will not appear in this series. And it seems the Red Sox want to avoid showing the Astros Sale, who could benefit from some time off. But would it be too much time? Sale could possibly have eight days off before pitching Thursday in Houston, but the Sox could always simulate a game before then.

Is the issue of overexposing your hitters or pitchers to an opponent overblown? That’s what we’re going to find out.

“I don’t know about all that,’’ said Red Sox first baseman Mitch Moreland. “I think nowadays everybody knows everything about everybody. The scouting reports are so precise on everybody, so I’m not sure if this situation is going to give anyone an advantage. I suppose it might for a pitcher. But even that’s a stretch.’’

Pitchers can always deviate from scouting reports. They could pitch the opposite of what a report says works against a particular hitter, just to throw the hitter off a bit. There are different ways to get around the familiarity angle.

This situation hasn’t happened very often. Not over a potential nine games.

The Astros actually were involved in something like this before. In the strike year of 1981, the Dodgers and Astros finished the regular season with a three-game series. They then met in the Division Series, which went all five games and was won by the Dodgers, thus playing each other eight straight games. In that season, the first- and second-half winners of a division played in a special Division Series, unlike the Division Series we now recognize.

“It was kind of uncomfortable situation for the players.’’ said former Astros reliever Joe Sambito, who pitched in those series. “Then it lingers into the playoffs. So, it’s tricky. The familiarity part is tough, too. You definitely know one another so you try to do things like not show your hand with your best guys if you can.’’

In 1991, the Blue Jays beat the Twins two out of three in the final series of the regular season, then played them again in the AL Championship Series, which was won by Minnesota in five games. That was potentially a seven-game series, so the teams could have faced each other 10 straight times.

The difference is that both the Twins and Blue Jays had clinched their divisions before the final series of the regular season, so both rested their regulars.

Those are the best examples of teams ending the regular season against each other and then facing off right away in the playoffs. In 2013, the Pirates and Reds played each other in the final series of the regular season, and then again in a wild-card game.

Red Sox manager John Farrell, while recognizing the oddity of the situation, said his team must focus on the prize — winning the division. It’s been difficult this week because of lousy starting pitching. He wouldn’t say he was concerned, but “it’s not the way you draw it up. We’ve gone through times where we’ve had these types of starts for a full time in the rotation.’’ Maybe it’s best they get it out of the way this week.

Right now, Sale is listed as the probable starter for Sunday. The Astros have Charlie Morton scheduled for Friday but are unsure about Saturday and Sunday.

“I wish I could control it more,’’ Hinch said. “This is not a spring training game. We have to attack it and compete to win the game. It’s important for them, it’s important for the AL East, it’s important for seeding. We’re still trying to catch the Indians.’’

The Astros executed their plan well. The Red Sox, not so much. This is a strange dynamic and the Sox are making it tougher than it needs to be.

Nick Cafardo can be reached at cafardo@globe.com.