Three months ago, when they were still tricking themselves into thinking they were a playoff contender, the Red Sox scored just one run over 27 consecutive innings in Baltimore, marking their lowest offensive output in a three-game series in 33 years.

Facing the Orioles again this week, they very nearly eclipsed that futility.

Until their five-run ninth inning in yesterday’s sweep-completing 10-6 loss at Fenway Park, the Sox had gone 26 innings with only two runs, both of which came on solo homers by rookie shortstop Xander Bogaerts. And while that is a sad referendum on the state of the Sox’ anemic offense, it also is a testament to the strength of the Orioles’ starting pitching, even if it’s impossible to name their ace.

Wei-Yin Chen? He took a perfect game into the sixth inning yesterday en route to his team-leading 15th win. Before this season, the 28-year-old lefty had a 4.04 ERA in just 55 major league starts.

Miguel Gonzalez? The 30-year-old journeyman (and former Red Sox farmhand) leads Orioles starters with a 3.22 ERA, but has only 29 career wins, nine of which have come this season.

Chris Tillman? Almost by default, he was the Opening Day starter. But the 26-year-old has blossomed into an honest-to-goodness top-of-the-rotation pitcher, going 17-5 with a 3.01 ERA since last year’s All-Star break.

We mention all of this because the post-Jon Lester/John Lackey Red Sox will be shopping for starting pitching this winter, and the division-leading Orioles might be proof that ponying up big money for proven No. 1 and 2 starters isn’t always the way to go.

“I think what the Orioles illustrate more than anything is depth,” Red Sox general manager Ben Cherington said yesterday. “That extends to and includes the pitching staff. They aren’t really getting elite performances from anyone, yet they have no holes either.”

Indeed, the Orioles are running away with the AL East despite the fact that general manager Dan Duquette’s biggest offseason acquisition has been a bust. Ubaldo Jimenez, who is making $11.25 million in the first season of a four-year, $50 million contract, has been banished to the bullpen with a 4.96 ERA, while Gonzalez, Tillman, Chen, Bud Norris and 23-year-old flamethrower Kevin Gausman are occupying the rotation for a combined cost of $10.9 million this season.

It helps that the Orioles have a shutdown bullpen and play impeccable defense, with Gold Glove winners at shortstop (J.J. Hardy), center field (Adam Jones), right field (Nick Markakis) and third base (Manny Machado, although he’s out for the season). But in Baltimore’s case, the whole of the rotation really is greater than the sum of its parts.

No wonder, then, that the Red Sox wanted to get good, long looks at as many of their own young pitchers as possible during the season’s final two months before deciding whether they really need to take a run at signing free agent James Shields or attempt to trade a package of prospects for the Philadelphia Phillies’ Cole Hamels or the Cincinnati Reds’ Johnny Cueto or Mat Latos.

Cherington reiterated yesterday that he “can certainly envision going in (next season) without a clear No. 1 (starter) if we felt good enough about the total group.”

Of course, it’s difficult to feel too good about Brandon Workman (5.47 ERA in 14 starts, including six runs in the third inning yesterday), Allen Webster (6.47 ERA in eight starts) and Anthony Ranaudo (5.40 ERA in five starts) based on the way they have pitched since getting a chance to take the ball every fifth or sixth day. Rubby De La Rosa (4.01 ERA in 16 starts) has been the best of an ordinary lot.

Given that fact, it seems likely Cherington will have little choice but to be active in the free-agent and trade markets. But the Orioles’ success has amplified the need to preserve as much pitching depth as possible, and in time, the Sox remain hopeful that there is a Tillman, Gonzalez or Gausman in the bunch, even if it comes from the next batch of prospects that includes Matt Barnes, Henry Owens, Brian Johnson and Eduardo Rodriguez.

“It’s not a question of whether a team benefits from having an ace,” Cherington said. “But you can’t always predict where the ace performance comes from.”

And as the Orioles can attest, it isn’t always the likeliest sources.