Fielder, not Pujols, may be top slugger hitting open market

Back in February, the story that dominated the early days of spring training was Pujols' failure to reach agreement on a contract extension with the Cardinals. A free agent after 2011, the best player in baseball set a February 15 deadline beyond which he would not negotiate. The Cardinals, according to SI's Jon Heyman, offered an eight-year contract worth more than $200 million, a contract that would have been a small premium over Mark Teixeira's salary and in line with the average annual value of Ryan Howard's extension. Heyman reported that Pujols was looking to be paid like the best player in baseball, with an eye on the contract the previous holder of that title -- Alex Rodriguez -- had signed in 2007: $275 million over 10 years.

At the time, there had been virtually no chinks in Pujols' armor in his 10 major-league seasons. He'd averaged 156 games a season and made just two trips to the DL, none since 2008. There'd been no indications of a decline in his game: his 2008, 2009 and 2010 seasons ranked among the five best in his career, and his skills indicators -- such as strikeout rate and basestealing effectiveness -- were all stable or improving. He'd established himself as one of the very best players in baseball history. That level of play and lack of decline made it reasonable to suggest that he might be worth up to $30 million a year for his age 32 through 39 seasons.

Now....chinks. First, Pujols had the longest slump of his career, batting .267/.336/.419 through the season's first two months, a stretch that featured an unusually high groundball rate and just six doubles. It served as the first hint of mortality, a reminder that Pujols could perhaps be subject to the effects of time. He shook off that poor start in June, hitting .317 with eight home runs -- nearly matching his combined April and May total of nine. Through five innings on Sunday afternoon, Pujols was 3-for-3 with a homer, and seemed invincible again. A poor throw by Peter Kozma and some bad luck quashed that notion and added more doubt. The freak play doesn't make Pujols "injury prone," but it does serve as a reminder of the risks involved in committing hundreds of millions of dollars across the better part of a decade to any player -- and how those risks do increase as the player ages.

Three months ago, Pujols seemed invincible. Now, we know he is not. We've seen him slump, and we've seen him walk off the field in pain, and we wait to see how he returns from an injury.

While all that was happening to Pujols, the player who was supposed to be the consolation prize was having nearly a perfect season. Prince Fielder, a bit more than four years younger than Pujols, has played in every game this season. In fact, Fielder has missed just 16 games in six full seasons in the majors. He's also having a monster year, leading the NL in homers and RBIs, posting career highs in batting, OBP and OPS, and doing all this in a season when offense is down around the league. While not a complete player -- Fielder's defense costs the Brewers a few runs a season, and he almost never steals bases -- he's established himself as one of the most threatening left-handed bats in the game. If form holds, unlike Pujols, he's going to be hitting the market off his best season, and the platform year -- the season before a player's free agency -- tends to have a disproportionate effect on the player's market value.

Before the season, Pujols' nearly-perfect career was enough to overcome the age difference between him and Fielder and make the case for him as a more attractive free agent. Before the season, Fielder's up-and-down performance -- his 2007 and 2009 were significantly better than his 2008 and 2010 -- was enough to invite questions as to his place in the game. Today, though, the most important piece of information may be this:

DOB, Albert Pujols: January 16, 1980

DOB, Pince Fielder, May 9, 1984

An age difference that could be handwaved away as recently as Opening Day now looms large over any comparison of the two players. Sign Fielder to an eight-year deal, and you're buying his age-28 through age-35 seasons, which are most of his peak and the early parts of his decline phase. Sign Pujols to an eight-year deal, and you're buying his age-32 through age-39 seasons -- all decline phase. Three months ago, the concept of a decline phase for Albert Pujols seemed silly, like worrying about him being run over by a unicorn. Now, we've seen what two months of struggle looks like, as well as the indelible image of him crouched in foul territory beside first base, wincing in pain.

As silly as the idea may have been in Florida in February, Albert Pujols may not be the most attractive free-agent first baseman on the market. The difference between his age and Fielder's, and the difference in platform-year performance, combine to make Fielder seem like a much safer investment. He will never have the value outside of the batter's box that Pujols will, but he may simply be so much better in it over the course of any contract that he's the better player. When you solve for X, you find that the difference in an eight-year deal is paying for the age-28 through age-31 years of Fielder versus the age-36 through age-39 years of Pujols. Based on the information at hand, what we know about aging curves and what we've seen from these players in 2011, it's very hard to justify treating the younger player as the less-attractive option. Pujols establishing himself as arguably the best first baseman in history up through age 30 does absolutely no good for a team signing him this winter. You don't get to play his old Strat-O-Matic cards.

We're going to get more information, and we need it. Does Fielder continue to be a disciplined hitter who rakes for both power and average? How does Pujols finish the season, particularly off an injury that could potentially affect his swing? Independent of the injury, can he continue the June surge that had started to wipe out memories of the worst two months of his career? Right now, though, the two players look to be much closer heading into the free-agent market than ever seemed possible, and there's an argument to be made that Fielder, rather than Pujols, is the pending belle of the ball.