FORT MYERS, Fla. – It is almost surely just a hypothetical exercise. After all, it would be shocking if the Red Sox and Adrian Gonzalez did not announce a long-term contract in the early days of the 2011 season that will keep the newly acquired first baseman in Boston for nearly all of the decade.

Even so, with the news that superstar Albert Pujols – who has commenced his career with one of the most dominant 10-year runs in major league history – and the Cardinals failed to reach an agreement on a long-term deal to keep the slugger in St. Louis, it does raise an interesting question.

If the Red Sox did not sign Gonzalez and instead waited until the offseason to negotiate with both free agents, which player would they rather have?

Based solely on career performance to date, it’s not even close. That’s no slight on Gonzalez – no one in the majors can surpass what Pujols has done in his career.

The Cardinals slugger has been an offensive force without compare since breaking into the majors in 2001. He’s hit .331 with a .426 OBP, .624 slugging mark, 1.050 OPS and 408 homers. Among players with at least 4,000 plate appearances in that time, he leads the majors in OPS, ranks second to Alex Rodriguez in homers, his slugging percentage is 40 points higher than any other major leaguer and he ranks second to Todd Helton in OBP.

Gonzalez, meanwhile, only became a big league regular in 2006 with the Padres. During those five seasons of everyday duty, he is a .288/.374/.514/.888 hitter with 161 homers and 501 RBI. For the sake of context, during that five-year period, Pujols has hit .33/.435 OBP/.628/1.064 with 207 homers and 609 RBI. 

But the comparison is not as one-sided as that. One talent evaluator considered the “who would you prefer” dilemma to be complicated, based on the fact that both players impact the game offensively while delivering Gold Glove-caliber defense.

Though Pujols’ offensive totals of the past five years appear far more impressive than Gonzalez’, there are a couple factors that shift the balance of the scales, particularly when projecting the performance of the two going forward.

HOME/ROAD SPLITS

The amazing Pujols has enjoyed nearly identical performance both at home and on the road in his career. He has hit .335 with a .433 OBP, .623 slugging mark and 1.056 OPS at home; on the road, he has a line of .328/.419/.626/1.044.

But Pujols has had the luxury of playing in parks that are largely fair to pitchers and hitters. Gonzalez? Not so much.

Petco Park is a terribly extreme pitchers’ park. Moreover, Gonzalez plays in a division with three ballparks (Petco, AT&T Park in San Francisco and Chavez Ravine in LA) that are havens for pitchers.

In the last five years, Pujols is a .326/.426/.633/1.059 hitter on the road with 113 homers; Gonzalez has marks of .307/.381/.579/.960 with 104 longballs. In the past three years, as Gonzalez has moved towards his prime, the gap has narrowed even more. Pujols is a .318/..422/.624/1.046 hitter with 68 homers; Gonzalez has 70 round-trippers and a line of .310/.390/.599/.989.

So, in stripping Pujols of his dramatic ballpark advantage (an advantage, of course, that is about to be eliminated as Gonzalez prepares for his first year in Fenway Park), even though Pujols’ performance is superior on the road in recent seasons, the dropoff to Gonzalez becomes shallower.

One side note – it is difficult to imagine whether Gonzalez or Pujols would benefit more from playing in Fenway. Gonzalez’ swing, as many have noted, is tailored to Fenway thanks to the loft he generates to the opposite field. Pujols, meanwhile, could well knock down the Green Monster if he took residence in Boston.

THE AGE-OLD ISSUE

Perhaps the even bigger issue is that of the two players’ ages. Assuming it would take a seven-year deal to land either player – a number that may be low for what it would take to sign either if they reached free agency – Pujols would be signed for ages 32-38, while Gonzalez would be under contract from ages 30-36.

So, both players would be spending their age 32-36 seasons with a club that signed them to a seven-year deal after the coming season. The difference is that a team would get two extra years of Gonzalez’ career prime (his age 30 and age 31 seasons), while Pujols would be under contract for two seasons of his late-30s (ages 37 and 38).

To put that difference in context: Since 1901, there are 54 examples of players hitting 40 or more homers at ages 30 and 31. There are just eight examples of players who have hit 40-plus homers at ages 37-38.

There are 222 seasons in which players with at least 502 plate appearances have had an All-Star caliber OPS of .900 or more at ages 30 and 31; there are just 28 such seasons for players between the ages of 37 and 38.

The difference is clear. The likelihood of great offensive numbers is much higher at the beginning of a player’s 30s than at the end of them, something that reflects both the possibility of increased injuries and a decline in skills over that decade.

That helps to explain why GM Theo Epstein and Sox officials noted frequently this offseason that the appeal of Gonzalez and Crawford was driven in no small part by the fact that both were in their 20s, with virtually all of their career primes in front of them. If you are going to push a pile of cash at a player, better that you receive as many of the best years of his career in return.

In that vein, it is worth noting that neither player is considered to have “young” bodies that would offer obvious cases to defy the aging process. Pujols is 6-foot-3 with a listed weight of 230 pounds. Gonzalez checks in at 6-foot-2 and 225 pounds.

These aren’t the fast-twitch athletes in the vein of Crawford, making the difference between their ages during the life of the contract perhaps even more significant. (Though it is also worth mentioning that speed is virtually irrelevant to both players’ games.)

DEFENSE

The age issue plays into a related concern that would exist over the life of the contract, chiefly, the question of what kind of defensive value both players might deliver over the life of their contract.

Right now, both are viewed as excellent defenders. Pujols won his second Gold Glove in 2010; Gonzalez won the award in 2008 and 2009.

But age takes an inevitable toll on defense, leading to an increased likelihood of being moved from a position to the role of DH. Because both Gonzalez and Pujols would be starting from extremely high levels, they would have quite a bit of potential defensive decline before they would no longer be adequate at the position.

Even so, because a Pujols deal of seven-plus years would be getting into an area where the risk of injury and breakdown increases, Gonzalez would be expected to provide greater defensive value, and the new Sox slugger would also be a better bet to stay in the field (and away from life as a DH) for the life of a deal. At a time when baseball front offices are placing tremendous emphasis on the sum of a player’s offensive and defensive contributions, that is a meaningful distinction.

MONEY

Maybe the outlook would change if Gonzalez were to sniff free agency. But it is worth noting that the two players have taken different tactics in their discussions of an extension.

Before Gonzalez was dealt by San Diego, his agent, John Boggs, publicly compared the first baseman to the market. In discussing the three-time All-Star’s worth, he was mentioned in the same breath as other players who received lucrative long-term deals: Joe Mauer (eight years, $184 million), Mark Teixeira (eight years, $180 million) and Ryan Howard (five years, $125 million).

Pujols, meanwhile, reportedly used the landmark 10-year, $275 million deal signed by Alex Rodriguez as a 32-year-old as his comp, and many have floated the idea that he would like to become the first $30 million a year player in the majors. So, if there were a disparity of perhaps $2 million to $5 million a year in what the players earned, that could be a significant aspect of a club making a determination about which player would be more valuable to them as a free agent.

POSTSCRIPT

Gonzalez is not Pujols. The Cardinals slugger is one of a kind, someone whose peers to this stage of his career reside in the innermost sanctum of Cooperstown. Gonzalez is elite, but he does not have a claim to such stature.

Still, one of the most fundamental principles of free-agent strategy is that players should be paid for future performance, rather than what they have already accomplished. In the instance of the two well-rounded, superstar first basemen whose current contracts only run through the coming year, there is not a guarantee that Pujols would deliver greater impact to a franchise over his next contract than Gonzalez might to his. As such, even though the exercise is unlikely ever to take place, if the Sox were to have the chance to pursue both players as free agents, there are many reasons to think that their priority would be the acquisition of the very superstar for whom they traded this offseason.