For the Sake of Comparison

Nothing is more common to spring training than the game of "Who does he remind you of?" Games are sleepy. Results don't count. Yet the future is on display right before us if we could only see it. So our minds wander to comparisons.

In Nationals camp, everyone asks similar questions. Is Ryan Zimmerman just a good player, or can he become a great one, a cornerstone of a contender? Will Lastings Milledge or Elijah Dukes become a star? Is it too late for Nick Johnson or Austin Kearns to fulfill their potential? Is Wily Mo Pe¿a a classic late-blooming slugger? And is anyone in the humble, injured Nats rotation capable of anchoring the staff of a winning team?

For generations, everyone from general managers to scouts depended on their eyes to divine the answers. Talk about "more art than science." Recently, Cardinals Manager Tony La Russa stood by the St. Louis batting cage, raving about the long arc of Chris Duncan's swing. "He's got as much power as anybody in the game. If you think that was beautiful, watch Rick Ankiel's action," La Russa said. "His hands are a blur through the hitting zone."

So they are.

In baseball, the eyes still have it. "We count on our scouts' opinion more than anything else," Nats General Manager Jim Bowden said yesterday. But important new statistical methods for making educated guesses about the future have arrived, too.

Now, it's possible to crunch the numbers of every player in history to see who most closely resembles whom at each point in their careers. For example, even without the customized special-project stat studies that teams such as the Nats commission, any fan can click on Baseball-Reference.com and, in a blink, see a list of the 10 players from the past who most resemble Ryan Zimmerman in offensive production at the same age. Or whose stats were almost eerily parallel to Chad Cordero at 25.

In the case of the Nats, some of the answers are shocking. It's no surprise that Zimmerman's offensive numbers after two seasons are virtually identical to hitters such as Cal Ripken, Ron Santo, Eric Chavez and Greg Luzinski. However, who would think Pe¿a's career, through age 25, compared plausibly with Albert Belle, Willie Stargell, George Bell and Jermaine Dye?

Or that Kearns, in a few years, might be similar to 30-homer 100-RBI Torii Hunter. That Felipe L¿pez strongly mirrors former Orioles standout Bobby Grich. Cristian Guzman's stats at 29 track those of Athletics shortstop Bert Campaneris, who excelled at 30, 31 and 32 in the World Series. Could Johnson still mature into an RBI machine like Tino Martinez? Surely, Dmitri Young can't have his best years past 34 like his stat-clone Paul O'Neill? And Johnny Estrada, after age 31, can't possibly turn into Elston Howard!

To be sure, many of these comparisons won't pan out. Plenty of Nats have career stats, to date, that duplicate players who later flopped. At 29, Nick Johnson and Travis Lee look like the same guy. Lee went straight downhill. Still, when you find two players whose batting average, on-base percentage and slugging percentage are very close at the same age, there's definitely a tendency for their careers -- assuming good health -- to be closely parallel in future seasons.

What's fascinating is that two or three of this year's Nats may actually develop into a Santo, Hunter or O'Neill.

"We do a lot of career comparison studies," Bowden said after hearing these examples. "It's definitely valuable. And it's cool."

When the Nats considered trading for Milledge, they not only studied his rookie stats for the Mets but "tried to estimate what he'd do in his first 500 big league at-bats based on his progress in the minors from A to AAA ball," Bowden said.