“I’m not talking today,” said David “Big Papi” Ortiz, his back turned to the media gathered around his locker in the Red Sox clubhouse as he pulled on a black, sleeveless T-shirt that displayed his powerful shoulders and bulging biceps.

That’s the only display of power Ortiz has had lately.

Because, in addition to not talking, he’s not hitting, either.

Not yesterday, when he went 0-for-4 and popped up weakly to first base for the final out with the tying run on base in a 2-1 loss to the lowly Texas Rangers.

Not lately, either — he’s gone 103 at-bats without a homer at Fenway, where he’s hit just three roundtrippers all season, and has only 12 hits in his last 56 at-bats over the last 17 games. In the last 20 games, he has hit just two homers and driven in only seven runs.

And he’s certainly not hitting the way he did last season, when he led the American League with a club-record 54 homers. Going into the All-Star break a year ago, Ortiz already had blasted 31 homers and driven in 87 runs. As the Red Sox try to salvage a split tonight in their four-game series with the Rangers (who came to Boston with the second-worst winning percentage in the American League) in what will mark the exact midpoint of their 162-game schedule, Ortiz has 13 homers and 49 RBI.

He left five men on base yesterday, two of them in scoring position, as the Sox were held to just one run for the second time in three games by the Rangers, who hadn’t held a team to less than two runs since whitewashing the Pirates on May 29, and had given up six runs or more in 14 of their previous 28 games.

It was bad enough when Ortiz flied to left in the fifth with one out and runners and first and second, and then struck out to end the seventh, again with runners at first and second.

The worst was in the ninth, when Big Papi came up in a situation in which he has had so much success in the past.

Five times last year, Ortiz had game-winning — and game-ending — hits, including three walk-off homers. One of those came against Texas, last June 11, so the Rangers could be forgiven if a sense of déjÀ vu hovered in the air as Big Papi came up to bat late yesterday afternoon with two outs, pinch-runner Julio Lugo on first, and the Sox trailing by just one run.

“Expectations are high when he comes to the plate,” said Sox shortstop Alex Cora. “It doesn’t matter what he’s done earlier in the game — when he comes up for that last at-bat, there are expectations for big things. It’s not fair, but he’s done it so often.”

He hasn’t done it lately, however, which is one of the reasons the Sox have been struggling — losing 5 of their last 6 games, 6 of 8 and 16 of 29, dating back to May 30.

“I don’t think he’s real comfortable,” Boston manager Terry Francona said of his suddenly slumping slugger.

But Francona stressed that he didn’t think Ortiz was pressing at the plate.

“You don’t stay 162 games feeling great about yourself,” Francona said. “But, as far as pressing, no. I know he feels a responsibility, but I also hope he comes up in that situation every time. That’s how we feel about him.”

Hard-luck loser Julian Tavarez, who was victimized by two errors that resulted in a run in the fourth, as well as by a lack of offensive support, said he isn’t worried about Big Papi, or the Sox.

“We’re going to be fine,” he said. “We know we’re good. We’re in first place because we’re good.

“We expect a lot from Big Papi. And why not? But it’s not only him. We expect a lot from everybody on this team. We’re not just counting on David. There are nine guys in the lineup. We expect everybody to produce.”

There wasn’t a Red Sox rooter in the jam-packed ballpark yesterday who didn’t expect Ortiz to come though in the clutch in the bottom of the ninth. He has done it so often, that people expect him to do it every time, forgetting that baseball is a sport where coming through even 3 out of 10 times is pretty darn good.

No one expects Ortiz to come though when it counts more than Big Papi himself. That’s why, even though it was announced yesterday that he once again had been voted the starting first baseman for the annual All-Star game next week, he didn’t want to talk.

The starting spot against the National League in San Francisco is an honor Ortiz richly deserves, but any pride he took in the selection was overshadowed yesterday by his disappointment in failing to produce the game-winning hit.

“This was a tough loss for him,” said third baseman Mike Lowell, who was one of five Boston players named to the A.L. All-Star team, joining Ortiz, Manny Ramirez, and pitchers Josh Beckett and Jonathan Papelbon.

After giving Big Papi a bit more time to cool off, several writers approached the usually affable Ortiz again.

“I’ve got nothing to say,” he said, his mood as black as his muscle shirt.

jdonald@projo.com