Terry Francona was ejected for the fifth time this season after he contested the overturned call on Kevin Youkilis.

AP / Frank Franklin II

NEW YORK — Like a storm whose full impact can’t be measured in the short term, it was too soon for the Red Sox to assess how much damage the Yankees inflicted with their series sweep, capped by yesterday’s 5-0 shutout.

If the Sox hold off the Yankees — their lead has been sheared to five with 28 to play — these three games will be viewed as merely demoralizing losses. If, on the other hand, the division title has been put back in play and the Yankees’ have been emboldened by their wins here, then the impact will obviously be much greater.

But yesterday, as they trudged out of Yankee Stadium, this much was unmistakable: The Red Sox lost an opportunity here.

“Oh, no question,” agreed Curt Schilling, the losing pitcher.

An opportunity to put the Yankees out of the running for first place in the division was squandered. So, too, was a chance to worsen their rivals’ wild-card chances and help ensure that they won’t have to meet them in the ALCS in October.

“We lost,” said Schilling. “We lost and got outpitched three days in a row.”

Only three days ago, the Red Sox led by eight, and the Yankees were reeling from a poor road trip that ended with an embarrassing 16-0 loss in Detroit the night before this series began.

But whatever edge the Sox had in momentum quickly dissipated.

“Both teams played exactly the opposite of how they had been playing before coming into the series,” Schilling said. “We didn’t play well (in the series) and they did.”

Schilling kept the Sox close, allowing only two solo homers, both to Robinson Cano — one in the third, another in the fifth. The first came on a fastball, the second on a hanging splitter.

Chien-Ming Wang, meanwhile, held the Sox hitless through six innings before the Sox showed some life in the seventh. Kevin Youkilis reached first when Derek Jeter’s throw from short pulled Jason Giambi off the bag.

With Giambi holding Youkilis on at first, Mike Lowell drove a pitch to right for the first hit of the afternoon for the Red Sox.

J.D. Drew then hit a roller to third. Alex Rodriguez charged the ball and attempted to tag Youkilis, who eluded the third baseman’s glove and advanced to third as Drew was thrown out at first.

The Sox thought they had runners at second and third with just one out. They were wrong.

The umpiring crew gathered and overturned the call, ruling that Youkilis had gone out of the baseline — replays indicated he had stepped on the infield grass — and the Sox were reduced to one baserunner (Lowell at second) and two out.

Terry Francona stormed from the dugout and got himself ejected for the fifth time this season. When Wang fanned Jason Varitek for the third out, both the inning and the afternoon were effectively over.

“I know it’s a judgment call,” Francona said. “What upset me was it was (second-base umpire) Derryl Cousins’ call and it was overturned by (third-base umpire Mark Carlson) without as good a view. That was frustrating. I think they should have used the (opinion) of the umpire with the best view.”

Explained Cousins: “On the play, we had a little lack of communication. I had a safe call for no tag. Carlson was making the call on (being) out of the baseline. We just had to get together to make sure we had it right.”

The Yankees piled on with three more off Hideki Okajima in the eighth and now head into the final four weeks with potential paths to October.

Asked to assess how the race had changed in the last 72 hours, Francona said: “I look at it that we lost today and we’re not very pleased about it …We need to show up and play the games and whatever our record is at the end of the season, that’s what it will be.”

That bit of Zen mastery may not do much to ease the angst felt by Red Sox fans who viewed this week as an opportunity to put the Yankees in the rearview mirror —permanently. But from where the Red Sox now sit, the Yankees are very much visible.

“We’ve spent all year playing it one at a time and turning the page,” said Schilling. “Now we’ll see how good we are at doing that.”

smcadam@projo.com