The trade of Marco Scutaro was treated throughout baseball as a confounding maneuver. The idea that the Red Sox were shipping the player who had been penciled in as their Opening Day starter seemed to make almost no sense.

It seemed like the sort of move the Red Sox never make: A salary dump.

After all, while the pitcher whom the Sox got back from the Rockies (Clayton Mortensen) could have value to the club, the primary motivation was clearly the creation of payroll space.

The Sox are not a team that typically dumps salary and sacrifices good players at one position in order to create financial flexibility to address needs at other spots on the roster. And so, the trade was treated with suspicion -- and reasonably so. Even if the Sox use the money freed up by Scutaro’s departure, it was hard to fathom that the team willingly went from stability to the unknown at shortstop.

That said, beneath the surface there were more dimensions to the trade than were immediately apparent and that help to clarify the Sox’ motivations in the deal.

WHAT WE DID NOT UNDERSTAND ABOUT THE MARCO SCUTARO CONTRACT

When Scutaro signed with the Sox in December 2009, the deal was assumed by virtually everyone who wrote about or discussed it to be a two-year, $12.5 million guarantee. The shortstop received a $1 million signing bonus and $5 million salaries in 2010 and 2011, with a $1.5 million buyout of a $6 million team option for 2012.

However, Scutaro also had an oft-overlooked player option of $3 million. The prevailing -- and accurate -- assumption was that there was little chance that he would end up exercising it.

Nonetheless, it had significant implications for how his average annual salary was calculated for luxury tax purposes, just as Adrian Beltre had a $5 million player option inserted into his one-year, $9 million contract for creative accounting purposes in the same 2009-10 offseason.

The player option was treated as a guaranteed year by Major League Baseball in calculating the average annual value of Scutaro’s deal, so rather than being a two-year, $12.5 million contract, for the purposes of determining how it would count against the luxury tax, it was actually viewed as a three-year, $14 million deal. That being the case, his contract accounted for $4.67 million against the luxury tax threshold (rather than the previously assumed $6.25 million) in both the 2010 and 2011 seasons.

However, the Red Sox’ efforts to minimize Scutaro’s impact on their payroll as determined for CBT (competitive balance tax) purposes in 2010 and 2011 -- both years in which the Sox paid the luxury tax -- were eventually going to come at a cost. Specifically, it meant that in 2012, his CBT number was going to increase significantly.

Ultimately, a player’s CBT salary over the life of his contract must match what he is actually paid. Scutaro had counted for a total of approximately $9.33 million in payroll (as calculated for luxury tax purposes) in the last two years. In 2012, the Sox were going to have to make up the difference.

That explains why it didn’t make sense for the Sox to decline his option. Had they done so, Scutaro’s deal would have been at two years and $12.5 million. That would have meant that, had the Sox declined their option, in the 2012 season, he still would have counted for $3.17 million against the luxury tax threshold (the difference between the $12.5 million he would have earned with the Sox -- $11 million in salary and a $1.5 million buyout -- and the $9.33 million figure for which he’d counted in 2010 and 2011).

Put another way: If the Sox had declined Scutaro’s option, they would have been on the hook for his $1.5 million buyout while also subjecting themselves to a luxury tax hit of as much as $1.27 million (40 percent of the $3.17 million 2012 CBT salary) for a player who was no longer theirs. That made little sense, particularly given that Scutaro was and is a solid contributor.

And so, exercising Scutaro’s option was something of a no-brainer. That said, for luxury tax purposes, he represented an expensive asset.

When the Sox exercised the shortstop’s $6 million option for 2012, it transformed his deal into a three-year, $17 million contract. That, in turn, meant that for the coming season, he would have counted for not just his $6 million salary for luxury tax purposes, but instead $7.67 million (the difference between the $17 million he’d make and the $9.33 million for which he’d counted in 2010 and 2011).

In dealing Scutaro to the Rockies, the Red Sox shed $7.67 million in CBT payroll for the coming year. For the Rockies, that’s an irrelevant consideration, since they’re not bumping up against the luxury tax threshold. But for the Sox, who are nearing the $178 million threshold, that CBT figure is a major consideration.

All offseason, the Sox had acknowledged that their ability to make moves was dependent upon their ability to create financial wiggle room. They have that now. The trade of Scutaro to Colorado freed up virtually all of the necessary CBT payroll flexibility for a hypothetical one-year, $8 million deal with, say, Roy Oswalt.

WHY NOW?

Two key factors led to the deal between the Rockies and Red Sox. First, the Sox found a team willing to take all of Scutaro’s salary. The Rockies, according to one major league source, were the first team to make such an offer this offseason.

The second element that played into the move was the fact that the offseason presented what the Red Sox considered opportunities to get better with the money freed by shedding Scutaro.

Oswalt, of course, remains on the market.

So does outfielder Cody Ross, the 2010 postseason hero who is capable of playing all three outfield positions and who owns a career line of .282 with a .349 OBP, .563 slugging mark and .912 OPS against lefties (with the caveat that he hit just .234/.336/.362/.698 against southpaws in 2011, and went from one strikeout per 5.8 plate appearances against lefties through 2010 to one per every 4.8 plate appearances in 2011).

The Sox also now can consider a trade for White Sox right-hander Gavin Floyd, who will earn $7 million in 2012 but will count for just $3.875 million against the CBT threshold in the last year of his four-year, $15.5 million deal (which includes a $9.5 million team option for next year).

Ultimately, the Sox reached the conclusion that they could improve by trading Scutaro and reallocating the $7.67 million CBT payroll figure for which he would have accounted.

BUT WHAT DID THE SOX GIVE UP, AND WHO PLAYS SHORTSTOP NOW?

Scutaro’s performance over the last two years was easy to overlook, but he was just about everything for which the Sox could have hoped when they signed him. Over the last two seasons, he hit .284 (fourth best among the 26 major league shortstops with at least 700 plate appearances in that time) with a .343 OBP (T-7th), .401 slugging mark (12th) and .744 OPS (9th).

That line was similar to (indeed, slightly better than) the one posted by a slightly more heralded peer in New York, Derek Jeter (.282/.347/.378/.725) and clearly superior to the one put up by Phillies shortstop Jimmy Rollins (.258/.331/.389/.720). In other words, though not an elite offensive shortstop, Scutaro was an extremely solid one.

Moreover, Scutaro was one of the most respected players in the Sox clubhouse thanks to his hardnosed approach, as well as one of the team’s few players who elevated his performance as the season was unraveling in September, a month in which he hit .387/.438/.581/1.019.

A couple of asterisks on Scutaro.

First, he spent quite a bit of time over the last two years either playing through or sidelined by injuries. He somehow managed to stay on the field for a career-high 150 games in 2010 even though neck problems that radiated through his shoulder and elbow made it almost impossible for him to lift his arm to throw.

In 2011, he again dealt with a host of ailments that included a stint on the DL for an oblique injury. Between the injuries and his temporary relegation to backup in the early season (at a time when Jed Lowrie was briefly the best hitter in the Sox lineup), Scutaro played in 113 games, his fewest since 2007.

He is a 36-year-old who has had chronic ailments. That being the case, while Scutaro does a tremendous job of playing regardless of his physical state, there are some health questions that make it fair to wonder whether how many games he can play.

Secondly, those injuries lessened his defensive abilities. He was something between an average and below-average defensive shortstop during his two years at the position in Boston, someone unable to replicate the excellence he’d delivered at the position in the prior two seasons in Toronto. Indeed, the Sox acknowledged last year that their left side infield defense was below average given the physical limitations of both Scutaro and third baseman Kevin Youkilis (who dealt with his own variety of ailments).

Scutaro’s overall skill set remained that of an average to slightly above-average shortstop -- and, it seems safe to say, the team’s best and most consistent performer at the position since Orlando Cabrera -- but not that of an irreplaceable star.

As their roster currently stands, the Red Sox expect Mike Aviles and Nick Punto to get the lion’s share of work at shortstop for them next year. For much of his career, Aviles has been a sneakily productive hitter, albeit one who sacrifices some of Scutaro’s on-base skill for a bit more pop.

In 38 games last year after the Sox acquired him in a trade with the Royals, Aviles hit .317 with a .340 OBP, .436 slugging mark and .775 OPS. In parts of four big league seasons, the 30-year-old is a .288 hitter with a .318 OBP, .419 slugging mark and .737 OPS.

Though he has played five positions (short, second, third, right field, left field), he has spent more time at shortstop than any other position. The Sox feel there’s a chance that he could be as productive offensively as either Scutaro or Jed Lowrie (whom the Sox dealt away to acquire Mark Melancon earlier this winter), but acknowledge that only time will tell whether that proves the case.

Defense, too, could prove an issue, as the Royals had moved Aviles off of shortstop since his rookie season, and he’s spent the last three years primarily at second and short (when not dabbling in the outfield). He actually received strong marks from publicly available advanced defensive metrics (such as UZR) at short in his 2008 season, but the scouting view of his work at the position is less flattering.

Punto, meanwhile, likely represents a defensive upgrade over Scutaro at shortstop, but his offense is limited, even after a year in which he hit .278 with a .388 OBP, .421 slugging mark and .809 OPS for the Cardinals. (His numbers, particularly his OBP, were inflated by spending much of the year hitting in front of the pitcher.)

All of that being the case, there is a decent chance that the Sox took a step back in terms of their production at shortstop in going from Scutaro to Aviles/Punto, but there is also a chance that it is not as great as has been portrayed (especially given the potential limitations on how much Scutaro can be expected to play).

And, if Aviles catches lightning in a bottle for the second time and returns to his 2008 rookie level -- when he had a higher OPS (.833) than Scutaro has ever had in any year of his career -- then there’s at least a chance that the Sox could even enjoy a slight improvement in their shortstop production.

Remember: The Sox’ goal is to get above-average production at every position. The bar at short, at least offensively, is set very, very low (.266/.321/.386/.708 among AL shortstops last year). In that context, an Aviles/Punto tandem would more than hold its weight if both players can come close to their production of last year.

One more thing worth remembering: The Red Sox led the majors in runs scored last year. Their top five hitters (Jacoby Ellsbury, Dustin Pedroia, Adrian Gonzalez, Kevin Youkilis and David Ortiz -- not necessarily in that order) are so good that, barring a cascade of injuries, they will remain at or near the top of the league in offense. They were 21st in the majors in runs allowed per game, suggesting that it is easier to improve the team by getting better run prevention than it is by adding offense. If a tradeoff needs to be made, and the Sox can move an average to slightly above-average shortstop for an above-average pitcher, or for a couple of above-average players, it's a net gain for the Sox.

WHAT DID THEY GET BACK?

In return for Scutaro, the Red Sox acquired Clayton Mortensen, who just concluded one of the more puzzling seasons one can fathom.

The No. 36 overall pick in the 2007 draft posted horrific numbers in 15 Triple-A starts for Colorado Springs, going 2-8 with a 9.42 ERA in 64 innings and a WHIP in excess of 2.00. But, in 16 major league appearances (including six starts), despite walking nearly as many (24) as he struck out (30), Mortensen held his own while pitching for the Rockies, going 2-4 with a 3.86 ERA in 58 1/3 innings.

One major league talent evaluator described the right-hander as a sinker/slider pitcher with a build that allows him to project as a starter, but whose stuff has seemingly plateaued. Given that, he is likely to define himself either as a future back-of-the-rotation starter or a middle reliever given his grounder-inducing sinker and what the evaluator characterized as “fringy” secondary pitches.

In other words, Mortensen seemingly looms as a pitcher capable of offering a team some roster depth, even if he doesn’t project as a central contributor to a pitching staff.

It is notable that Mortensen does have an option remaining. The Sox have a shortage of pitchers who would permit them the flexibility to shuffle them between Pawtucket and the majors this year, at a time when 40-man roster members such as Andrew Miller, Michael Bowden, Felix Doubront, Scott Atchison and Franklin Morales are out of options.

Mortensen represents a pitcher whom the Sox can summon for a spot start or a week in the bullpen and then send him back down to the minors. He and Junichi Tazawa are the only two major league-ready pitchers on the 40-man roster who permit the Sox that kind of latitude.

Clearly, the payroll flexibility was the Sox’ primary motivation for the deal. That said, the player whom they got back did address a roster shortcoming for the Sox.

ARE THEY BETTER?

That’s that bottom line. Are the Red Sox a better team in 2012 without Scutaro at shortstop and with whatever player or players they will acquire with their newfound payroll flexibility? In order to figure that out, the other shoe has to drop.

Until the rest of the Red Sox’ offseason takes shape, it will be hard to say -- even on paper -- whether the Sox have improved. If, for example, they acquire a mid-rotation starter and sign an outfielder with the money, an upgrade is realistic. If they stand pat, do nothing and pocket the money (unlikely, but who knows?), then it would be difficult to make the case for the deal.

As such, the deal is a reminder that it is virtually useless to evaluate an offseason on a move-by-move basis. Just as it was easy to decry the Sox’ willingness to let Jonathan Papelbon go -- only to see the team add Melancon and then Andrew Bailey -- it makes sense to take a wait-and-see approach to assessing moves.

Taken individually, one could draw the conclusion that the Red Sox under new GM Ben Cherington are careening from move to move as if driving in a bumper car. But the reality is that, when one views the moves in their totality, there may be a route with more definitive direction that is being methodically charted.

Still, the destination of that route (and whether, ultimately, it will represent an upgrade over the 2011 club) is not yet apparent, and will remain unclear, it would seem, until the Sox arrive in spring training. Even so, for those who have proclaimed the recent Scutaro deal to be madness, there does appear to be method behind it.