Manny Ramirez strikes out swinging with two men on to end the game yesterday, something that has happened far too frequently this season.

The Providence Journal / Bob Breidenbach

BOSTON — In a span of a few hours on a steamy afternoon, the Red Sox’ flaws were prominently displayed for all to see.

In the grand scheme of things, the Red Sox’ 6-5 loss to the lowly Devil Rays didn’t cost the Sox in the standings, for while the Sox’ late-inning comeback stalled, so too did the Yankees’.

But as the season rolls into the final six weeks, the Red Sox keep tripping over the same issues.

They seem incapable of beating pitchers with whom they’re unfamiliar.

Yesterday’s beneficiary was rookie righty Andy Sonnanstine, who was facing the Sox for the first time. Typically, such matchups favor the pitcher, but the Red Sox take this to an extreme.

Manager Terry Francona has said repeatedly that this problem isn’t exclusive to the Red Sox, that most teams have difficulty against pitchers they’re seeing for the first time. But this seems more like an anecdotal problem for the Sox.

Sonnanstine handcuffed the Red for the first six innings, limiting them to only two hits and a walk before tiring in the seventh.

After the game, the Sox offered generic praise for Sonnanstine — “He threw strikes … mixed his pitches” — but it was clear that he hadn’t beaten them with overpowering stuff.

For that matter, Sonnanstine hasn’t dominated many other lineups this season. Though regarded as a pitcher with some promise, he came into yesterday with a 1-8 mark and a 6.35 ERA.

For a lineup with so many veteran hitters, the Sox should have broken through. But the team didn’t make the necessary adjustments, and once Sonnanstine established himself, he was able to retire 14 of the first 15 hitters he faced.

That’s because …

Lately, the Sox’ offense has been invisible until the last few innings of games.

In winning Tuesday night, the Sox were held scoreless until the ninth inning. The night before, in the series opener with Tampa, they had one run in the first, and then didn’t score again until the seventh.

The same was true during the weekend series in Baltimore. Until the Sox rallied against the Orioles’ bullpen last Friday, they were blanked over the first seven innings. And in the series finale Sunday, another loss, they scored three runs in the first three innings, but spent the rest of the afternoon stranding baserunners and wasting opportunities.

When the bullpen imploded in the late innings, the Sox didn’t have the cushion they should have had, resulting in a dispiriting loss.

This late-starting offense adversely affects the pitching staff, since starters are forced to make perfect pitches in order to protect slim leads — or worse, pitch from behind on the scoreboard — rather than attack hitters with the comfort of a lead.

Those kind of stressful innings put extra wear-and-tear on a staff, while keeping opposing starters in the game longer, a lose-lose proposition.

The hallmark of the successful Red Sox teams from 2003-2005 was the ability to wear down a pitching staff by getting to the bullpen early and beating up opponents’ long relievers, ordinarily the weak link of most staffs.

But not anymore.

Finally, there’s the continued absence of late-game clutch hitting from the two lineup mainstays, David Ortiz and Manny Ramirez.

Beginning in 2004, Ortiz alone could once be counted on to produce a half-dozen or so walk-off hits. But there have been precious few heroics from the Sox’ DH this season.

Maybe it’s his knee, or his shoulder, or some combination of both, that has reduced his ability to drive the ball. But whatever the reason, Ortiz is not the same force late in the game.

Though he earned a ninth-inning walk yesterday, putting the potential winning run on base, Ortiz has had 54 at-bats in “late and close” situations — defined by a team winning by a run, tied, or with the potential tying run on deck — and has knocked in just five runs all season.

Ramirez, who doubled home a run in the eighth then struck out in the ninth for the final out of the game, stranding two, is no better. Ramirez has 55 at-bats and has also delivered five, while striking out 14 times — or about once every four at-bats.

A number of people — from Francona, to Julio Lugo, to Jason Varitek — all said the Sox had the people they wanted up at the plate in the ninth.

But based on this season, did they?

smcadam@projo.com