The Yankee offseason so far has begged one obvious question: which is the better duo - Matsui and Damon, or Johnson and Granderson?
To find that out, we need to divorce ourselves from emotional attachments to Johnny Damon and Hideki Matsui (assuming Damon does not return). They were very good players while in the Bronx, and helped end a decade-long title drought, but to continue to be a perennial powerhouse, emotions can't get in the way of sound baseball and business decisions. It's the job of GMs to look to the future, not the past.
2009 saw Matsui and Damon post impressive numbers: .274/.367/.509 and .282/.365/.489 respectively.
Johnson and Granderson put up lines of .291/.426/.405 and .249/.327/.453 respectively.
At first glance, it looks like this will mean a drop in production. But let's dig a bit deeper.
M & D played in the new Yankee Stadium, also known as the most homer-friendly park in baseball (26% more longballs than the average park). The newcomers, J & G, played in gigantic parks: Comerica Park, Nationals Park and Dolphin Stadium, all of which are known as pitchers havens. We can reasonably assume M & D's power numbers will drop, only because they're moving to less 'left-friendly' ballparks. Conversely, J & G's power numbers should see an increase hitting toward the famous 'short porch.'
Johnny Damon is coming off one of his best offensive seasons, but the Yankees should be wary of players (1) in contract seasons having career years, and (2) having career years at 35. We can naturally expect Damon to regress. On the other side, Curtis Granderson will be 29, coming off an unusually down-year. 2007 was a career best, 2009 was (nearly) a career worst: we can naturally expect something in between (like 2008: .280/.365/.494, nearly identical to Damon's 2009, only Grandy did it in a pitcher's park).
Matsui is less unlikely to repeat his year, which was closer to his 'norm' than Damon's was. However, Nick Johnson's ridiculous .426 OBP is immensely valuable. I expect both Matsui's SLG and Johnson's OBP to decrease, only because they're rather out of line with their career averages. But I do expect Johnson's SLG to increase, what with the short porch in rightfield and the protection of Tex and A-Rod - he should see more hittable pitches and fewer walks.
Then there's defense, where J & D have, and should, easily surpass the aging duo of M & D. Matsui didn't play one inning in the field this year. It was the condition of his knees, not his salary, that gaves the Yankees pause. The Angels promised to give Matsui a chance to play the field at least once or twice a week. That's something the Yankees could not do. Damon played a passable leftfield, but every other outfielder on the team could play a better leftfield (yes, even Swisher), and are a minimum of seven years younger.
Granderson is a natural centerfielder, and wherever he plays he'll provide average to excellent defense. He'll also be playing in a significantly smaller centerfield than he's used to. Johnson is a solid first-baseman and will fill in admirably when Tex needs a day off. If Tex is going to last another seven years (while still bringing quality production), he'll need consistent rest.
Matsui was almost worthless on defense. Joe Girardi didn't even play him during the World Series - that's how little confidence he had in Matsui's ability to play the field. Damon is a mediocre leftfielder at best; a fulltime DH at worst.
Then there's health. Johnson has suffered from countless injuries in his career. He's played more than 130 games just three times in eight years. What will hopefully keep him healthy is a fulltime DH role. He's been in the NL the last five seasons, so perhaps not having to dive for grounders more than once a week will keep him healthy and productive all year. Conversely, can you really see Hideki Matsui playing the outfield several times a week? If he does, it'll only increase his chances of injury. Johnson and Matsui are pretty much even on the 'injury risk' scale: Johnson is incredibly susceptible to 'freak' injuries, and Matsui has chronically aching knees. Which is worse?
Damon and Granderson are also roughly equal in terms of health. There are no worries about Grandy, who's averaged 154 games over the last four seasons, or Damon, who's averaged 144 games over the same span. And do I need to mention that J & G are six years younger than their counterparts?
In terms of WAR, which takes into account all aspects of a player's game (offense, baserunning, defense, position, playing time), M & D were worth 4.8 WAR/season over the last three years. J & G were worth 5.9 WAR/season, and that's after giving Nick Johnson a zero for 2007 when he didn't play one game. So even if he stays just moderately healthy, it should be a net gain in wins.
Then there's cost. J & G will make $11 million combined next year (plus potential incentives for Johnson). M & D will probably make about $15 million ($6.5 million for Matsui, probably about $9 million for Damon). That saved money can be spent on another starter (Sheets, Duchscherer, Bedard), which is more important, at this point, than another hitter. Also, not having to commit several years to Damon allows that money to be spent on the amazing free agent class of 2011 (Mauer, Lee, Beckett, Webb, Crawford,) and bring back fan-favorites Jeter and Rivera.
For a cost conscious club, which the Yankees are looking more like everyday, the recent moves make for a more efficient team going forward. Younger, cheaper, and at least as productive.
(With all that said, I do believe, for the record, that Cashman was surprised at how fast Matsui got snatched up. He didn't see much of a market for 36-year-old fulltime DHs. When Matsui signed with Anaheim, Cash had to act quickly or all the good hitters would be gone. There weren't many other options, but Nick Johnson was the best fit for the Yankees. I'm very happy he's with us and not against us (as in, on the Red Sox).
Regarding Damon, I believe part of the reason Cash traded for Granderson was (1) to get a good, young centerfielder allowing for the departure of Damon, and (2) to put pressure on Damon/Boras to accept a short-term deal. Unfortunately, it wasn't enough, and it took negotiating with Nick Johnson to get them to cave, only by that time it was too late.)