I find it fun that Conor Jackson, Adrian Gonzalez, and James Loney are in the same division. The three have similar skill sets and all fall into the class of player that is typified by players of recent vintage such as Mark Grace, John Olerud, Sean Casey, Keith Hernandez, and the early career Rafael Palmiero. All 3 have a history of being very capable when it comes to putting the bat on the ball, sending liners into the gaps. All have had questions surrounding how much power they would produce due to line drive swings. Gonzalez and Loney are both plus defenders and while Jackson isn't any great shakes in the field, I think he'll be alright in the long run.
Jackson is the oldest of the trio, having been born one day before Gonzalez in 1982. He's also the only one who was drafted out of college. He's also had the best K rates and walk rates as a pro.
The isolated slugging percentage is actually a bit impressive in the minors, but it's knocked down a bit by the fact that he went through a lot of hitters parks on the way to Phoenix. Lancaster, El Paso, and Tucson are all outstanding places to be a hitter.
Gonzalez is the one who has demonstrated the most power thus far. He had a nice power spike with San Diego after some people had written him off a player that would never post adequate power numbers.
Loney is the enigma of the group. He's the one who isn't locked in as a major league regular yet. He's 2 years younger than Gonzalez and Jackson. He's currently the one who also plays some outfield. And he has an injury history that is much longer than either of the other two.
PECOTA has some interesting comps for the trio. Ed Kranepool and Chris Chambliss shows up on all three top 20 lists. Gonzalez himself is number 2 on Loney's list after...Kranepool. Kent Hrbek, Justin Morneau, and Gus Bell are all on the Loney and Gonzalez lists. Paul Konerko, Bob Watson, and Mike Ivie are shared by Jackson and Gonzalez. As a rule, these lists are eccentric collections of players. Some of the names on the lists, such as Daryle Ward (#4 on Loney's), Mo Vaughn and Jason Giambi (10, 11 on Jackson's), and Dave Nilsson (15 on Gonzalez's) are terribly informative for this comparison. I do like the collection of players that are shared on the lists as they're illustrative of similarities shared by these 3 young players and tell of the different paths their careers might go down.
Bob Watson is a nice, solid middle baseline. He had a nice run with the Astros as their starting left fielder for the first half of the 70's and then their starting first baseman for the second half before spending his decline phase. In his New Historical Baseball Abstract, Bill James ranks Watson as the 33rd best first baseman of all time, just behind Steve Garvey and Mark Grace, who strangely enough are two of the very first names that cross people's minds when they think of the skill set that players like this possess. The meat of Watson's career was between 1971 and 1978, where pretty much every year he posted a BA over .300, took a good number of walks leading to OBP's generally in the .380-.400 range, and hit approximately 20 home runs annually with a small spike during his peak between '75 and `78 to the mid/upper 20's. And the Astrodome at that point was a very extreme pitcher's park.
Most people are pretty familiar with Chambliss. He haunts the dreams of my fellow Royal fans. He was basically Watson, only less so, posting lower batting averages, fewer home runs, and fewer walks. Hrbek's a good idea of what happens when somebody comes up with this skill set and starts hitting for more power. Fellow Twins player and current AL MVP Morneau fits there as well. Gus Bell was a center fielder back in the 1950's who had a short, but pretty damned good peak from '53 when he broke out with a .300/.354/.525 line while playing a league average center field. Kranepool is what you'd be betting on for any of these guys if you took the "under" on their "over/under" gamble. He had a long career for the Mets, but he never hit for any kind of power and spent most of his career as a part-timer, finishing his career with 5436 career at bats of .261/.316/377 production. Ivie bounced around for a decade or thereabouts, and hit 27 home runs for the Giants in '79, but for the most part, he was more Kranepool than Watson. We're all familiar with Konerko.
PECOTA's long range and short range forecasts for all three project fairly stable commodities and doesn't go out on a limb for any of them. Gonzalez and Jackson get "they are what they are" forecasts with a weighted mean forecast of .289/.355/.481 with a .287 EQA. It doesn't forecast much growth through his peak years, as the highest EQA in his 5 year forecast is a .290. Jackson is more of the same, as it sees a .294/.380/.481, .286 EQA and a couple of very small bumps in 2008 (.296 EQA) and 2011 (.295), but essentially flat growth curves. Loney is projected beneath the 2 established guys, but still likes what it sees in him. .295/.351/.470, .278 EQA would be acceptable in a Dodgers lineup that will probably need steady OBP when (not if) Nomar misses a couple months because of some kind of malady. It likewise doesn't see much growth in Loney over the next half decade, forecasting seasons that are pretty much a carbon copy of what it saw in him this season.
So here's my analysis of the three taken individually. Gonzalez by all measures a pretty good starter right now and it's hard to see a circumstance where he isn't a key part of Padres teams for many years to come. Hitting 24 home runs is a remarkably good sign given the extreme nature of Petco Park, especially against lefties. His walk and K rates coupled with his isolated slugging have trended more and more over the last couple years towards the slugger demographic and away from the Mark Grace/John Olerud class of hitters. Maybe we should have seen this coming when his ISO spiked at Oklahoma City in 2005, as he posted a .223 ISO. It wouldn't surprise me much to see him continue in that direction and end up as more of a .280 hitter who gives you 30 home runs a year. His glove will be a huge asset as he's always received a lot of respect for his skills with the glove and the stats back that up. Maybe he is the guy we all thought Sean Casey would be back when he broke in during the late 90's.
Jackson hasn't ever had that power spike and he doesn't have the plus defense, but he does have a long history of posting impressive walk and K/BB rates, which makes him a potential threat to post abnormally high BA and OBP figures even if he remains a high teens/low 20's per season home run threat. If he does add some power, he could be a beast, posting very high OBP's as pitchers avoid grooving a pitch to him and he sits back and lets them give him a free pass. Edgar Martinez is what can happen when those factors converge.
Loney is the wild card. He has less of a record and I trust Las Vegas hitting numbers about as much as I trust people on infomercials who claim they can cure fatal diseases but the FDA won't let the secrets get out. He's had an injury history that probably has held his power numbers down a bit. However, none of them were chronic, and he shouldn't have any long term effects. He had a wrist injury on a HBP. He broke a finger sliding into second, and then finger after that became infected. And he had a relatively minor knee contusion. I'm not particularly fond of the Garciaparra contract primarily because it blocks Loney, who is ready for prime time and would have sufficient backup in Olmedo Seanz and the option of temporarily moving Jeff Kent over to first and Wilson Betemit to second. As it is, Nomar will probably provide about the same production as Loney would at a much higher price and will probably miss a significant amount of time due to injury. Meanwhile Loney will have to hope for either that inevitable Nomar injury or for the complete collapse of the Luis Gonzalez/Delwyn Young platoon. I think PECOTA may be a bit more conservative about Loney's bat than what I'd be. There's maybe a 10-20 percent chance that Loney takes off and becomes a stud, about that same percentage chance that he stagnates and becomes the next decade's answer to Eric Karros, and the rest of the scenarios I can envision consist of him doing pretty much exactly what PECOTA forecasts, becoming a good OBP source who never is really All Star caliber.
If given the choice, my favorite of the group is Jackson. For fantasy leaguers, he'll be helped by playing in a good hitter's ballpark. You rarely can go wrong with the guy who best controls the strike zone. Loney probably has the most upside given his youth. Gonzalez is a sure thing to be a good player though.