BOSTON — When it happens every once in a while, it’s expected. When it happens a few times, it’s a trend. When it goes on for as long as it has, it’s downright troubling.

For the last month, the Red Sox have had difficulty scoring runs. And while it hasn’t cost them greatly in the standings, it has cost them some games. Including yesterday’s.

Limited to nine hits and a solo run, the Sox lost to the Texas Rangers, 2-1, the 13th time this year, and the eighth since June 5, that the Sox have mustered two runs or fewer.

“You go through cycles where it seems like scoring runs is very difficult,” said manager Terry Francona. “We’ll straighten it out and we’ll put a bunch up. It’s frustrating on a day like today because we’ve got enough pitching and we’re having a tough time putting runs across the plate.

That would seem to be an understatement. In dropping five of their last six, the Sox have scored two runs or fewer three times. And against the Rangers, who came into the series ranked next-to-last in the American League in ERA, the Sox have scored just one run over the last 16 innings.

The lone sign of life yesterday came in the fifth when singles by Alex Cora, Dustin Pedroia and Kevin Youkilis accounted for the only Sox run. Otherwise, they were unable to break through, leaving a runner on third in the fourth, and two runners on in the first, seventh and eighth.

For the game, Red Sox hitters were a woeful 1-for-9 with runners in scoring position. For this series, which concludes tonight, the Sox are 5-for-34.

A one-out walk to Pedroia brought David Ortiz to the plate in the ninth, representing the winning run. But Ortiz popped out to first, stranding a runner and typifying the Sox’ ineptitude in scoring chances.

“We’re not having the kind of at-bats were capable of,” said shortstop Alex Cora.

Julian Tavarez was the tough-luck loser, allowing just one earned run in 5 2/3 innings. Then again, Tavarez might be accustomed to the non-support. In nine of his 15 starts this season, his teammates have scored two runs or fewer.

“It’s not always going to work for you,” said J.D. Drew of his team’s offensive malaise. “It’s just the way the baseball season is. It’s so long. There are times when you just can’t find your stroke. But all of a sudden it will all come back.

“When our pitching staff only gives up a couple of runs like this, we need to score more runs. We have to find a way to get some more runs. We know what we’re capable of. We’ve got a good lineup, up and down. It’s just a matter of getting going again. You don’t know what it’s going to be. But then something just clicks and you’re off.”

Not soon enough for a team that is two games under .500 since June 1, just about the time the offense went into hibernation.

smcadam@projo.com