NEW YORK -- It’s no secret that the decision to commit $150 million to Josh Beckett and John Lackey in an ill-fated five-month stretch impacted the Red Sox dramatically for years to come.

Because the Sox committed to those two right-handers, their hands have been tied -- at least concerning the rotation -- for the last two years. The team stacked all of its chips on Beckett and Lackey. That bet placed, the team did not have the freedom to pursue other top starters such as Cliff Lee, C.J. Wilson, Mark Buehrle or Yu Darvish on the open market.

But really, the most significant consequence of the commitments to Lackey and Beckett wasn’t the sacrifice of the opportunity to play in the deep end of the free agent pool. After all, every long-term deal for a pitcher in his 30s (obviously, Darvish represents an exception to that) comes with considerable risks. There are no safe bets when it comes to long-term deals for pitchers.

The real opportunity cost to the Sox in committing so much to Beckett and Lackey was not in the other high-end free agent options. Arguably the most significant blow to the Sox was the foregone opportunity to pursue pitchers like Hiroki Kuroda, the Yankees right-hander who dominated the Sox and Beckett in New York’s 4-1 victory on Sunday night.

Kuroda shut down the Red Sox completely over eight innings in which he yielded four hits and one earned run, striking out four and issuing nary a walk, using his slider for swings and misses and his sinking two-seamer to get a ton (13, to be exact) of groundouts. The performance was not an aberration.

“This is how good he's been,” Yankees manager Joe Girardi said. “He has been on a tremendous roll for us.”

Kuroda struggled early in his transition from the Dodgers to the Yankees but has been dominant for roughly three months now. In his last 16 starts, he is 9-2 with a 2.22 ERA. Overall, he is 12-8 with a 2.96 ERA, the seventh-best mark in the American League.

The Sox, obviously, would love to have such a pitcher. Indeed, they would have acquired him at the 2011 trade deadline had he not used his no-trade veto power to prevent a deal with the Dodgers. At the time, the right-hander said that he did not want to leave the West Coast.

(Intriguing game of revisionist history: How different would Red Sox history have been if Kuroda had accepted the trade and reinforced the rotation? Would the Sox have won two more games and reached the playoffs? Might a spot in the postseason have resulted in a decision to exercise Terry Francona’s two-year option? If that had happened, might it have resulted in a sense of well-being in the Red Sox organization that either would have led all of the clubhouse scandals of last season to be kept in-house or that might have instead turned them into a charming form of eccentricity? Such is the nature of the fact that the Sox missed the playoffs by one game a year ago.) 

But last offseason, Kuroda was open to negotiating with teams on the East Coast, including the Red Sox. And the Red Sox certainly were interested, viewing his mix of a proven track record (he had a 3.45 ERA while averaging 175 innings a year in his four seasons with the Dodgers) and stuff as a very interesting option for the rotation.

Despite their interest in the pitcher, however, the Sox never were in position to make a competitive bid for the right-hander before the Yankees swooped in and locked him up in January on a one-year, $10 million deal. The commitments to Beckett (four years, $68 million), Lackey (five years, $82.5 million), Daisuke Matsuzaka (six years, $52 million -- plus a $51 million posting fee) and, to a lesser degree, Jon Lester (five years, $30 million) and Clay Buchholz (four years, $29.45 million) left the Sox with all of the agility of the Titanic steaming toward an iceberg.

Hence, the Sox weren’t able to take advantage last offseason of a winter that turned out to be an excellent one for bargain shoppers. Kuroda (one year, $10 million), Edwin Jackson (7-8, 3.69 ERA; one-year, $11 million deal with the Nationals) and Bartolo Colon (10-9, 3.43 ERA; one-year, $2 million deal with the A’s) -- among others -- were available on short-term deals.

But the Sox, thanks to their already enormous payroll (and, more specifically, having maxed out their spending on the rotation) could do little in the winter aside from signing a few pitchers (Aaron Cook, Carlos Silva, Vicente Padilla) to minor league deals. Pursuing Kuroda would have required the team to clear payroll in the form of more trades; in retrospect, perhaps that would have been a better course to chart, but salary-shedding trades are cumbersome and often challenging.

After all, it wasn’t until last Jan. 21 that the Sox were able to find a trade partner willing to take on Marco Scutaro’s salary. That was eight days after Kuroda had agreed to sign with the Yankees.

“Taking advantage of the best value in free agency is important,” one AL talent evaluator said. “Last winter happened to be a pretty good one to get one-year values on starting pitchers. [The Sox] weren’t able to take advantage of it.”

Again, that is a reflection of the fact that the Sox created little room to maneuver by clogging their roster (for better and worse -- obviously, some of these are very good deals for the team) with starters on multi-year deals. In the last five years, the Sox have signed five starters to multi-year deals: Lester, Lackey, Beckett, Tim Wakefield (two years, $5 million after the 2009 season) and Buchholz.

By contrast, the Yankees have remained surprisingly streamlined. They’ve made huge commitments to CC Sabathia twice (first on his original seven-year, $169 million deal, then on a five-year, $122 million extension to prevent him from opting out after three years), and they also pushed a five-year, $82.5 million deal to A.J. Burnett.

But those have been the only multi-year commitments to starters made by New York. As such, the Yankees have been in position to add and subtract pitchers virtually every season, and to let prospects come up when they’re ready. The results have been impressive.

The team has enjoyed excellent bang for the buck from pitchers like Kuroda, Colon, Freddy Garcia and Andy Pettitte (now on his third one-year deal in four seasons) while also adding a key homegrown starter in Ivan Nova. There have been some pitchers who haven’t worked out (Javier Vazquez, acquired in a trade with one year left on his contract, and Michael Pineda, acquired from the Mariners before reaching arbitration eligibility), but because the team has avoided long-term deals, those never prevented the club from changing the mix.

(It’s also worth noting, of course, that the Yankees do continue to enjoy deeper pockets than the Red Sox. That gives them greater flexibility to pay top-dollar for one-year deals -- for instance, to sign a Pettitte in reaction to the Pineda injury -- than the Sox possess. Still, despite the fact that the Yankees enjoy greater resources, it would be hard to argue that their expenditures on starting pitcher have also been more efficient and flexible in recent years.)

Philosophically, the two rivals have taken different approaches to building rotations. That makes the disparity of their results all the more interesting.

The Yankees have seen their starters’ ERA improve in each of the last four seasons, from 4.58 in 2008 to 3.98 this year. By contrast, the Sox have had their ERA go up in three of the last four years, from 4.02 in 2008 to 4.82 (26th in the majors) this season.

And now, the Sox face the challenging prospect of needing to improve the performance of their rotation despite the fact that -- aside from Matsuzaka -- the team once again will have limited flexibility this coming offseason. Beckett remains under contract for two more years; Lackey has two more years on his deal (plus a vesting option at the big league minimum for a third); Lester has another season on his contract plus an option; Buchholz has three more years and two options on his deal.

Matsuzaka will come off the books this winter, giving the Sox a bit more room to maneuver. Nonetheless, the Sox will have to spend part of the winter exploring the lengths to which they would consider going to dump one or more members of the rotation (presumably Beckett or Lackey, given that Buchholz and Lester remain affordable and talented).

Before Sunday’s game, Sox general manager Ben Cherington insisted that he had faith in Beckett (and Lester, for that matter) to enjoy improved results going forward. Though the Sox are 7-14 in games started by Beckett (who fell to 5-11 with a 5.23 ERA), Cherington suggested that the Sox rotation can get better even without altering the personnel mix.

“It’s no secret. Our starting pitching has not been as good as it needs to be if you look at the entirety of the season so far,” Cherington said. “Part of improving it has been to get our guys get back close to where they’ve been in the past. [Beckett and Lester] are key guys. If there’s other ways to improve it this offseason, we’ll look at that, but there’s a lot of performance upside with the guys here, without adding anything to it. So it’s our job to help those guys, get the most out of them. I know it won’t be any lack of effort on their part.”

But as a model for how to build a rotation, there’s likely less grounds for reassurance in hoping that underperforming pitchers (and, in Beckett’s case, pitchers with visibly diminished stuff) in the middle of long-term deals can alter their fortunes than there would be in the ability simply to move on and find someone else. That is a formula that the Yankees have found to be a winning one, and that the Red Sox have been unable to pursue.